There is no evidence that a  terror suspect fatally shot following the stabbing of two police officers planned to behead the officers, Victoria’s top cop says.

Chief Commissioner Ken Lay told ABC radio that police had information Numan Haider, 18, was talking to others before Tuesday night’s attack outside Endeavour Hills police station.

“There’s some information that he was certainly talking to other people around the time,” he said.

“It’s certainly something we’re pursuing.”

Lay said it was unclear whether others might have dropped him off or were waiting for him.

“That’ll be clarified in a little while,” he said.

Lay dismissed claims Haider may have intended to behead the police officers.

“There is nothing, absolutely nothing, that I’m aware of that would suggest that was the intention,” he said.

“Having said that, there were some really worrying pieces about this young man’s behaviour that we are working through.

“It’s not helpful to be making these great leaps based on speculation.”

Lay said police are “quietly and methodically” working through evidence.

Police say the officer had no other choice after the known terror suspect repeatedly stabbed an Australian Federal Police officer and the leading senior constable who shot him.

Haider, of Narre Warren, had been seen at a shopping centre displaying a flag linked with jihadist group Islamic State, or ISIL, and last week had his passport cancelled on national security grounds.

Meanwhile, more information has emerged about Haider’s activities before the attack this week, with counter-terrorism officers increasingly concerned about this behaviour and escalating rhetoric.

The terror suspect’s passport was cancelled a week ago on national security grounds but police say they weren’t about to arrest him when he turned up for a pre-arranged meeting at a Melbourne police station.

Within moments of shaking his hand, the two police officers were stabbed and Haider was shot dead. A second knife was found on his body.

“His actions may tell a story of what his intentions were,” Victoria Police chief commissioner Ken Lay said on Wednesday.

There were also unconfirmed reports he had a black flag linked to jihadist group Islamic State, or ISIL.

The Narre Warren man had been on the police radar for three months, but authorities say he was acting alone when he violently lashed out at the police.

“This is an incident resulting from the actions of one individual,” Victorian Premier Denis Napthine said.

“It is not about faith, it’s not about ethnicity, it’s about the alleged behaviour of an individual.”

Fairfax Media reported Haider may have planned to behead the officers, after ISIL on Monday issued a statement asking its followers to directly target Australians and citizens of other western countries. Police declined to comment.

The incident comes a week after Australia’s biggest counter-terrorism raid, involving hundreds of officers, unearthed allegations of an IS-driven plot to abduct a member of the public and film him being beheaded.

Officers had become concerned Haider’s behaviour had escalated in the past week, and he had been seen in a shopping centre displaying an IS flag, Lay said.

“We learned of some behaviours that were causing us significant concern and our interest was greatly heightened,” he said.

But Lay said the joint counter terrorism taskforce officers did not intend to arrest Haider.

“We were just needing to have a chat and we just wanted to test some of his thinking,” he said.

Haider came willingly to the Endeavour Hills police station on Tuesday night, but wanted to meet the police in an adjacent car park.

After shaking hands, Haider repeatedly knifed the Australian Federal Police officer in the stomach, head and neck and the Victoria Police leading senior constable was stabbed twice to the forearm, police said.

The Victorian policeman then fired a single shot, killing Haider on the spot.

Haider’s family had tried to prevent him from leaving their house on Tuesday and were concerned for his safety, the ABC reported.

But contrary to some reports, AFP acting commissioner Andrew Colvin said Haider hadn’t made any “specific” threats against Prime Minister Tony Abbott.

The Islamic Council of Victoria (ICV) has already received a number of threats since Tuesday’s incident.

“Threats, language against the family of the young man, clearly there are – and I use this deliberately – extremists on all sides of the community,” ICV secretary Ghaith Krayem said.

Krayem said the black flag being used by IS has a deep historical significance for Muslims and had been co-opted by the group.

“Right now that flag poses a real point of sensitivity, and somebody who was thoughtful and mature would not be going around waving the flag,” Krayem said.

Krayem said he would wait for investigations to conclude before judging Haider’s actions.

“I’m not going to condemn what he did because we don’t know what he did,” he said.

Abbott, who has travelled to the US for international meetings on the response to IS, said the incident underscored the need for police and community vigilance.

“Obviously, this indicates that there are people in our community who are capable of very extreme acts,” he said.