Indika never even made it out of Colombo airport and was jailed straight away. So when the police van came and parked on the sandy road outside his home, Sumith came — peaceably, his wife insists — to the front door.

“They took him inside this house, and they beat him,” Leena tells The Age as she sits on the porch of the brightly-coloured bungalow of their family home.

“He was on the floor, they were kicking and punching him. They hit him with batons. His son Suhas, who was four, was upset, and ran into the kitchen to get a weapon, a knife, to stop them hitting his father.”

The police took no notice of the boy and took his bloodied father away.

Nearly two years on, he and Indika are still in jail. They have never had a trial. Police say they are part of a people-smuggling racket, but that case has never been made before a court.

Leena says their only crime was running from threats against their lives, their only mistake choosing to flee to Australia.

Their case is not unique, nor an anomaly. Sri Lankan asylum seekers rejected by Australia and sent home say they have been arrested, imprisoned without trial, and tortured.

With about 150 Tamils now in the Australian detention system who face involuntary return to Sri Lanka, an Age investigation has uncovered instances where people sent home from Australian soil, or stopped by the Australian government from ever reaching the country, have been returned to systematic, state-sanctioned abuse.

One man told The Age he was arrested at Colombo airport and held, without trial or charge, for 55 days. During his interrogation, he says he was hung upside down and beaten with batons in an effort to extract a confession that he was a member of the separatist terrorist organisation, the Liberation Tigers of Tamil Eelam, better known as the Tamil Tigers.

A Sri Lankan police spokesman has denied all allegations, saying claims of maltreatment are politically motivated and that there is no torture.

In the case of Sumith and Indika Balapuwaduge, who are Sinhalese, they had fled to Australia in 2008, claiming political persecution. They had quit the local branch of the ruling coalition, the United People's Freedom Alliance and joined an opposition party.

They say they were beaten by their former colleagues and told they would be killed. They paid 200,000 rupees ($1465) each for passage on a people smuggler's boat and reached Australia, but after nearly a year on Christmas Island they were forcibly removed — by plane — to Sri Lanka.

Members of Sri Lanka police's Criminal Investigation Department were waiting at the airport. Both were interrogated, and accused of being part of the smuggling ring that organised the voyage. The brothers denied any involvement but Indika was immediately jailed.

With Sumith later jailed alongside him, the brothers have endured regular beatings and undergone continuing interrogation, sometimes together, sometimes alone, according to their family.

They have yet to face a trial. It was more than a year before they were even charged — they now face only minor immigration offences for leaving the country irregularly.

The Age was in court in Marawila last week when the brothers were appeared before a judge. They appeared healthy, but Sumith's wife Leena says their incarceration and the ongoing uncertainty over their case has destroyed their family.

“[Sumith's son] Suhas is especially traumatised by all of this. He saw his father beaten and taken away from him, and now he only sees him behind bars in the prison cells in court,” she says.

“Financially, the situation of our family is very poor. The breadwinners of our family are not here, and we have to keep finding money for the lawyers to try to get them out.”

Appearing in court might be seen as progress but Sumith and Indika have been through these machinations many times before.

Led from the prison bus handcuffed to a chain linking them to 30 other prisoners, they wait in the cell at the back of the large, whitewashed courtroom, waiting for their names to be called.

Their case lasts barely five minutes — a representative of the Attorney-General's Department isn't present in court — and is adjourned again, until October. They don't speak.

Afterwards, Leena says that even if Sumith and Indika are released soon, the family will continue to suffer. “Our family can not live freely again, we live in fear every day.”

There are other cases, too. A 29-year-old Tamil man, whose name The Age has chosen not to reveal, says he also lives in fear of being arrested and tortured again.

In October 2009, Sarath * was one of 254 asylum seekers on board a 30-metre wooden cargo boat headed for Christmas Island when prime minister Kevin Rudd personally telephoned Indonesian President Susilo Bambang Yudhoyono asking the Indonesian navy to stop it.

It was taken to the Indonesian port of Merak, where the asylum seekers staged a sit-in protest. With a gravely ill mother at home, and seemingly no end to the impasse, Sarath got off the boat and was returned to Sri Lanka.

He, too, says he was arrested at the airport, and interrogated by the CID. Because he was from Sri Lanka's north, he was accused of being a member of the Tamil Tigers.

Sarath says he was never a member or supporter of the Tigers. He says he fled his home village when the Tigers took control of it, and escaped being conscripted by the Tiger's army by explaining he was his mother's only child.

After questioning by police – including on the notorious fourth floor of the CID's Colombo headquarters — Sarath claims he was handed over to the defence ministry's national intelligence bureau.

“They hung me upside down with ropes and put a pole behind my arms, then they hit me with batons. They hung me upside down at 11am and they took me down at 3pm. They hung three of us up, but only two of us came down alive. The other man died.”

Upside down and bleeding, Sarath claims he was asked, over and over, to reveal where the LTTE had hidden their arms caches at the end of the war. He told them he didn't know.

Sarath was released after 55 days, but remains, he says, under constant supervision. On the day The Age meets him, we are forced to change plans at the last minute, because plain-clothes police were watching his front door.

He still suffers crippling headaches, “from where I was kicked in my head”, and walks with a limp because of injuries inflicted on his leg.

The accounts detailed given to The Age are in accordance with the findings of human rights groups, and the UN which said in a recent report it was concerned by allegations of “widespread use of torture and other cruel, inhuman and degrading treatment of suspects”.

Human Rights Watch Deputy Asia Director Elaine Pearson says her organisation has uncovered more than a dozen cases of asylum seekers returned from Britain being tortured.

“We've documented cases of at least 13 people who've been returned to Sri Lanka, all Tamils, and who've faced arbitrary arrest, torture, in some cases rape, by government officials upon their return.”

She says countries like Britain and Australia should not be deporting Sri Lankan Tamils back to the country where they continued to be persecuted.

“Those who are sent back, particularly anyone with links to the LTTE, are at risk of being arrested and detained and are at risk of torture.”

BUT Sri Lankan authorities deny torture is condoned by the government, or ever used against returned asylum seekers. Police spokesman Ajith Rohana say the Tamil diaspora is trying to damage Sri Lanka's reputation around the world and foment unrest within the country.

“These people are told to give a bad image of Sri Lanka, by the people smugglers who make money taking people across the ocean. They are told to pretend they are being ill-treated and discriminated against. It is not true.”

He says while returned asylum seekers are interviewed at the airport, they are never maltreated.

“No, this (torture) does not happen, this is not correct. There are strict laws regarding illegal immigration and people have to be accountable for breaking the law, but this (maltreatment) does not happen ever.”

A senior official with Sri Lanka's Department of Immigration and Emigration, who spoke on condition of anonymity, told The Age reports of torture were forged.

“Sri Lanka doesn't have any legal system of punishing returnees, whether by arresting them or torturing them. They are free to live a normal life.

“Such cases are highlighted by interested asylum seekers in order to convince foreign governments that they can't live in peace here and should be granted asylum.”

The Australian government says it does not return anyone it was obliged to protect under international laws.

“However, all irregular maritime arrivals found not to be owed protection will be removed from Australia, and we are satisfied that the removal of failed Sri Lankan asylum seekers in those circumstances does not breach Australia's international obligations,” a spokesman for the Department of Foreign Affairs and Trade says.

He says it is not unusual for returned Sri Lankan asylum seekers to be interviewed at the airport by authorities, but that a member of the Australia's immigration department, or of the International Organisation for Migration, was usually present.

“Australia condemns all forms of mistreatment by law enforcement authorities. We have a well-established and robust dialogue with Sri Lanka on human rights issues.”

The immigration department last week moved a Tamil man into detention in Melbourne, in preparation for his deportation to Sri Lanka.

Bala Vigneswaran from the Australian Tamil Congress says his organisation had helped lodge about 150 appeals for judicial review of failed refugee claims — with ministerial discretion the last possible step before deportation should those reviews fail.

In Colombo, human rights campaigner Ruki Fernando says Australia must stop returning Sri Lankans until their safety could be guaranteed.

“This is still happening. Sri Lanka is a country where people who are returned are likely to be tortured.

"Australia can not run away from its obligation to protect the people it sends back here,” Mr Fernando said.

* Sarath is not his real name.

Ben Doherty is South Asia correspondent.