07/04/2017 12:56 PM AEST | Updated 07/04/2017 3:51 PM AEST

Counter-Terror Police Investigate Fatal Service Station Stabbing, Attacks In Queanbeyan

Two teenage boys, aged 15 and 16, have been arrested over the incidents.

The fatal stabbing of a service station worker in Queanbeyan on Thursday night is being investigated for potential links to terrorism, police say.

Two teenage boys, 15 and 16, were arrested on Friday over a string of attacks, including the stabbing death of a 29-year-old Caltex worker. Physical evidence from the scene of the service station attack led a joint counter-terrorism taskforce -- comprised of NSW police, ASIO and Australian Federal Police -- to investigate the 16-year-old for a "possible link to terrorist activity".

Deputy Police Commissioner Catherine Burn told media on Friday the joint counter-terrorism team is focusing on the 16-year-old suspect's "modus operandi", that authorities believe could be indicative of a possible terrorist attack.

"We've arrested a 16 and a 15-year-old, and from the sources of information, it appears at this stage that there may be links to a modus operandi that we would suggest is indicative of a terrorist attack, inspired or otherwise," she told reporters on Friday.

"At this point the 16-year-old is the person that we are having a closer look at in terms of the sources of information that we have recovered only in the last couple of hours."

Burn also confirmed police found physical evidence at the scene of the crime that suggests the incident could have been a possible terrorist attack, although refused to say any links have been confirmed between the suspects and Islamic State.

"Certainly there was physical evidence at the scene which does go to our view that this might be an act of terrorism. However, I can't go into the details clearly of the evidence," she said.

"These people have not been charged, they are juveniles, and it is still in an investigative stage, but there was physical evidence.

"We don't have concrete evidence. We do have information which indicates to us that there is some possible linkages to some terrorist activity. The extent of that is unknown."

The Australian Federal Police and the NSW Police Force have also said there is no ongoing threat in relation to the matter and that hte community should continue to go about their daily lives.

Prime Minister Malcolm Turnbull has condemned the "shocking" attacks as he confirmed the involvement of counter-terrorism police.

He also offered his condolences to the family of the man who was killed.

"We send our prayers and best wishes to the two other victims of that evening who were assaulted by the two youths," he said in a press conference on Friday afternoon.

"The circumstances have raised sufficient concern -- as I have discussed with the Commissioner of the AFP, Andrew Colvin -- to warrant the involvement of the joint counter-terrorism team."

A 29-year-old man was stabbed multiple times at a Caltex service station in Queanbeyan, near the NSW-ACT border, just before midnight.

When the man's colleague arrived for his shift, he found the man lying on the floor. He was unable to be revived and died at the scene.

The teenagers are also believed to be behind assaults on three other men in separate attacks nearby. A second stabbing victim was taken to Canberra Hospital in a serious but stable condition. Another man was allegedly hit over the head with a beer bottle and a fourth was assaulted with a tyre iron.

The two teens have been taken to a watch house in Canberra but police plan to seek their extradition back to NSW today, according to ABC News.