Police are still trying to identify a man who died after being shot with a Taser early yesterday, while he was being arrested for a robbery he may not have committed.
It is believed the man may have been aged in his mid-20s to mid-30s and from South America.
CCTV captures Taser incident
RAW VISION: The moments before a man died during an incident in which he was Tasered and capsicum sprayed by police in Pitt Street, Sydney. (No sound)
Officers investigating the robbery of a convenience store in King Street in Sydney's CBD tried to arrest the man in Pitt Street about 5.30am yesterday.
Police said the man resisted arrest and officers used capsicum spray and shot him with a Taser.
The man stopped breathing and emergency services could not revive him, police said.
The acting Assistant Commissioner, Mark Walton, told a news conference yesterday police had been responding to reports of a robbery.
"It's unclear as to the involvement of this man or the extent of that actual incident," he said.
"Whether it is a robbery or not is unclear at this time. The report of a robbery is ongoing and I cannot … even confirm that it was an actual robbery."
This morning, police said they could not comment on media reports the man had gone into the King Street store seeking protection and had stolen a packet of biscuits on his way out.
A staff member at the convenience store on King Street said today that a colleague told him a man had tried to enter the shop twice yesterday about 5am.
The staff member, who asked not to be named, said the man walked into the enclosed cashier area and was chased away, but returned 10 minutes later.
He leapt over the half-door of the enclosed area and was pushed out and back on to the street.
The staff member added that his colleague told him the man had been frothing at the mouth and appeared to be on drugs.
Acting Commissioner Alan Clarke could also not say how many times Tasers were fired or how many officers deployed their weapons during the incident.
"All those details will be dealt with in due course," he told ABC Radio today.
"It's a complex investigation.
"There are a number of avenues we need to look at."
The death has sparked renewed criticism about the use of the electroshock weapon. The NSW Council for Civil Liberties has called for an immediate moratorium.
But Mr Clarke said people should not jump to conclusions.
"I think it is very presumptuous for anyone to determine the cause of death is a Taser simply because it's occurred in an incident where a Taser has been utilised," he said.
He said there were "very strict" guidelines surrounding the use of Tasers and that they were not used often.
"Among 16,000 police officers we are using the Taser less than once a day," he said.
"We couldn't say that every time we use a Taser it has saved us from using a firearm.
"[But] there's no doubt that police prefer to have an option less lethal than a firearm."
NSW Council for Civil Liberties president Cameron Murphy said the danger was that police were inclined to draw their Tasers simply because people did not comply with directions.
Police now had an array of weapons, including Glock pistols, batons and capsicum spray.
"It is a worrying thing when police may opt to use one of these weapons and that increases the risk of injury or death," he said.
There was concern that capsicum spray, which increased the heart rate, and the Taser, which also affected the heart, might combine to cause heart failure.
Greens MP David Shoebridge said there had been an escalation in Taser use since their introduction, but there was no reduction in the use of firearms.
A critical incident investigation team, with officers from the Homicide Squad, has been set up to investigate the death.
The investigation is being reviewed by officers from the Professional Standards Command.
Investigators appealed for the public's help in identifying the man, who was described as being of medium build, 178 centimetres tall, with brown eyes and brown shoulder-length curly hair.
He was wearing Diesel Industrie blue denim jeans and a white Gap brand short sleeve shirt.
Anyone with information about the man's identity is urged to phone Crime Stoppers on 1800 333 000.
Taser-related deaths in Australia
October 4, 2010 - A man died after being Tasered by police in the chest. He was hit once by the Taser probes as he ran at two officers while allegedly carrying two long-bladed knives at his Sefton home. Police had been investigating reports he sexually assaulted the woman with whom he shared the Helen Street unit.
June 12, 2009 - A 39-year-old man died after Queensland police repeatedly stunned him with a Taser at a property at Brandon, near Townsville. Officers said the man was acting violently and was a threat to himself and police.
May 2002 - Gary Pearce, a violent, mentally-ill 56-year-old, died about two weeks after being repeatedly shot with a stun gun when he threatened police after barricading himself inside his inner-west Sydney home. Mr Pearce, a heavy smoker, had a long-term heart disease, a thyroid problem and hepatitis C.
- with AAP, Glenda Kwek and Malcolm Brown