Marungul Avenue in Ngunnawal is usually a quiet residential road, where many neighbours know each other by name, and, according to residents, nothing much really happens.

But that changed on Thursday night, when a swarm of police descended, strung police tape from letterboxes, and warned residents to pack their bags and be ready to leave.

Earlier in the evening, officers executing a search warrant near Wanganeen Avenue came across a “significantly suspicious” package, and called in the bomb squad.

An exclusion zone of about 100 metres was established, and police began to warn 48 residents in 25 homes of an impending “operation”; some were told to pack their bags and be ready. Others weren’t given any warning, and were told if they had somewhere to go, it was time to leave.

“I was freaking out a bit,” said one woman, Lisa, who took her two young children to stay with her mother.

“We were in a bit of a hurry, a rush to get out of here. And when we left there were police everywhere … I think I left without shoes on, and we all had our pyjamas on.”

Another resident, who asked not to be named, said she was “very surprised” when police asked her to leave with her partner and baby – especially after seeing coverage of the bombing in Boston on television.

“We were somewhat scared,” she said. “We didn’t expect it to get that serious.”

Kalie van de Burgt, who lives a few houses up from the area being searched, said she came home from the movies after her husband called to alert her.

“The street was full of police, and there was a bomb squad truck and forensic. We didn’t really know why, but they said pack your bags, and if we come back and tell you to go, be ready to go,” she said.

They packed and prepared their six-month-old baby and their dog Millie, and waited until police said it was time to leave. Ms van de Burgt said they were surprised it was happening on a street where she knows many of her neighbours by name, but she never felt scared.

“This doesn’t usually happen on our street,” she said. “[But] I felt really safe because the street was just packed [with police]. You know something’s going on, but they’re looking after you at the same time.”

About 2.30am, the bomb squad detonated the device, prompting reports of a “loud bang” on social media. Detective Sergeant John Giles said police couldn’t identify the package, but confirmed it was part of an ongoing weeks-long investigation.

“It certainly wasn’t by its nature a bomb, but it is certainly a product that wouldn’t be found normally in a person’s home,” he said.

The woman who lived in the home police searched was an “innocent party”, Detective Sergeant Giles said, but confirmed police had identified a suspect.

Police did not anticipate finding similar devices as their investigation continued.

“We made the determination early enough that people could make arrangements with friends and relatives,” Detective Sergeant Giles said. “The residents were fantastic."

The street was deemed safe shortly after 5am.

As Ms van de Burgh drove back home on Friday morning, her birthday, she noticed a new, large, black smear burnt into the road near where police had been searching the night before – the only real reminder of a burst of excitement in an otherwise silent street.