Victoria’s police chief commissioner says the terror raids in Sydney and Brisbane show again that state and federal authorities are on top of things.

ISIS supporters in Victoria are known to police, who are taking steps to monitor their risk, according to the state’s top officer.

Chief Commissioner Ken Lay said there are no direct links between Victoria and Thursday’s terrorism raids in Queensland and NSW.

But ISIS supporters exist in Victoria and they are being monitored closely, with police doing a lot of work to ensure the community is safe, he said.

Former ASIO director general David Irvine has said a number in the “tens” have returned to Australia after fighting with extremist groups in Syria.

“We have a proportion of those people back in Victoria, I’m not going to be specific about the numbers,” Mr Lay told reporters on Friday.

“Rest assured, we know who those people are and we’re taking appropriate steps to understand exactly their risk level and ensuring that we understand where they are, what they’re doing.”

Mr Lay said he has been comforted that security and police agencies have been able to keep abreast of security risks.

“Australia’s shown it has a good track record of addressing these issues and understanding what the risks are,” he said.

“If there is intelligence or evidence to suggest these raids need to occur, Australians will see them occurring.”

Mr Lay said Victorian police command is in close contact with national agencies.

But he urged Victorians to continue going about their daily lives.

“Go about your life as you normally would,” he said.

“Should there be specific risk that we need to advise the community about, we certainly will.”

However, he added that anything out of the ordinary should be reported to triple-zero.

Mr Lay said he had met with the AFL and Melbourne Cricket Club chiefs to work through risks, with more police to monitor big events.

“Any of the major events over the next six to seven months, we’re working with the organisers to take all possible precautions, understand the risks, understand how we can make people feel safe,” he said.