Reports say one person was stabbed to death and two other injured in a mosque at Dallas in northern Melbourne when a group of elderly men objected to a 22-year-old man trying to get inside the Broadmeadows Turkish Islamic Cultural Centre, where the elderly men and women were meeting.

The Age reports that forty worshippers witnessed the stabbing attack, in which a Glenroy man, said to be in his 70s, was fatally stabbed, as he along with two other men tried to stop a 22-year-old man from entering the Centre, around 11 am on Thursday.

Detective Senior Sergeant Stuart Bailey says the young assailant was in an agitated state.

"Three people in that mosque tried to prevent him from entering. They are all in their 70s," he said.

"The male has produced a knife and has stabbed all three of them," Mr Bailey said.

ABC reports that when the police sergeant arrived at the scene, he too was assaulted by the man.

"Fortunately for police the critical incident response team (CIRT) were also nearby and attended. They deployed capsicum spray which didn't stop the offender," Detective Bailey said.

The assailant then ran towards the mosque's parking where he was tasered.

It took six of the CIRT members and two uniform police officers to finally subdue the man, the officer said.

The Age reports that among the two injured, is a Craigieburn man who is said to have suffered injuries to his upper body. He was taken to the Royal Melbourne Hospital and is said to be in a critical condition. The third victim is a man from Mickleham who has been admitted to the Northern Hospital and is reported to be in a stable condition.

Detective Bailey said there were several elderly Turkish women who witnessed to the incident and have been left shaken by the "horrific attack". He told reporters that it was too early to say what the motive of the attack was, whether the attacker was affected by drugs or whether the attack was motivated by religion.

The police have, meanwhile, confirmed that all three victims and the assailant were of Turkish origin.