Melbourne teenager believed it was okay to behead people

A teenager shot by police after stabbing two officers believed that anyone who insulted the prophet Mohammed should be beheaded, an inquest has heard.

Numan Haider, 18 was shot and killed outside Endeavour Hills Police Station, in Melbourne's south-east, in September 2014.

During today's coronial inquest, a friend of Haider's, Ali Torkmanyer who helped him obtain weapons, described the argument the pair had shortly before he attacked two detectives, the ABC reports.

"He said something about if someone was to say something bad about our prophet it was okay to behead them," Mr Torkmanyer told the coroner’s inquest.

"It is not a normal conversation to have."

A recording of a phone call between Mr Torkmanyer and another man was played during today's inquest in which Mr Tormanyer said Haider wanted to purchase a large knife, a smaller pocket knife and a taser for protection as he was going to start dealing marijuana.

“If I knew anything about him wanting to hurt police ... I would have done my best to stop him," Mr Torkmanyer said.

"At the time, that was the last thing on my mind - that he'd use it against someone.

"I didn't see him as an aggressive person.

"Numan seemed like a joker and was always kidding around. He was not really serious."

Mr Torkamanyer said he did not associate with Haider's friends anymore.

The inquest continues.