Beside a quaint sports field and gentle creek, the area was closed off by tarpaulin deep into the afternoon as forensic detectives tried to unravel a string of crime scenes throughout the city.

Police, called in from nearby towns, cordoned off areas awaiting analysis from detectives as unnerved neighbours came to grips with the alleged 14-hour spree from two teenage boys that left one man dead and three in hospital.

"I'm in massive shock, what's happened is horrendous," said one Karabar resident who heard the squeal of tyres in the morning as the suspects fled the second stabbing on Barracks Flat Drive.

The man, who didn't want his name revealed, couldn't believe the trail of destruction left in Queanbeyan.

"I'd understand it happening in Sydney or Melbourne or one of the bigger cities, but not here," he said.

Nearby residents Robyn Hunter and her daughter, Maddy, were equally shocked by the reported gory nature of the crimes and the investigation into terrorism links.

"I was a bit surprised by that, you don't expect Queanbeyan to be involved in something like that, especially our little area up here," Mrs Hunter said.

Alan Webber, owner of the Caltex store where the fatal stabbing took place, said he was still coming to terms with the crime after only learning the identity of the victim through the media.

"We're all terribly upset and feel for his family and the others involved at the service station," he said.

Mr Webber said Mr Akbar had limited family in Queanbeyan, with most living at his home in Pakistan.

"We can just say a prayer for his family and the boy who found him as well.

"It's certainly a very sad day for everybody involved ... it's a terrible, terrible tragedy."

The suspects were arrested in the ACT a short time later "without incident", Superintendent Rod Smith, from the Monaro Local Area Command, said.

"It doesn't need to be said, but it doesn't get more serious than this," Superintendent Smith said.

"It's an absolutely horrific series of events, and we'd just like to reassure everybody that there are two people that we believe are involved, and both of those people are currently in custody."

Queanbeyan-Palerang Regional Council administrator Tim Overall expressed his "shock and sadness" at the events and thanked both NSW and ACT police for their work in apprehending the suspects.

"I extend my deepest sympathy to family, friends and colleagues of the young man who lost his life and others who have been affected and traumatised by the events," Mr Overall said.

ACT Minister for Police and Emergency Services Mick Gentleman reassured Canberra residents that law enforcement were prepared to deal with crimes such as these.

"ACT Policing have strong well tested plans and resources to effectively respond to any event that threatens the safety of the ACT community, and I have full confidence in their handling of this matter."