Ambulance response times have blown out in Victoria with overworked paramedics taking sick leave because they cannot cope with what one whistleblower says is a dangerous system.

A paramedic, who did not want to be identified, said there was "no doubt" the lives of patients were being put at risk as callers were often forced to wait one to two hours for an ambulance, with one caller on the weekend enduring an eight-hour delay.

"The risk to everybody is not just unreasonable but dangerous," he told Radio 3AW.

The whistleblower said a lack of resources meant paramedics were unable to control a scene at Langwarrin, in Melbourne's south-east, following a car crash in which six people were injured just after midnight on Sunday.

A Victoria Police spokeswoman said police were examining the accident scene when one of the injured men tried to assault a firefighter.