* Four police officers were hit and killed by a truck as they were dealing with a speeding Porsche on the Eastern Freeway, Kew, 5.40pm Wednesday

* The officers were leading Senior Constable Lynette Taylor, Constable Glen Humphris, Senior Constable Kevin King and Constable Josh Prestney

* Constable Humphris and Constable Prestney had only recently graduated from the police academy

* The Porsche driver had tested positive to a roadside drug test and two of the officers had decided to impound his car and called for backup

* Shortly after two other officers arrived, the truck ploughed into all four, travelling about 100km/hour when it hit

* The truck driver had a medical episode and is in hospital under police guard

* The Porsche driver ran from the scene but has been identified as a 41-year-old man who is known to police, believed to be Richard Pusey

* He was arrested on Thursday and is being interviewed by homicide detectives

* Police raided the truck driver's Cranbourne home on Wednesday night and are yet to reveal what they found

* On Thursday morning one of the bodies of the fallen officers was taken from the scene

* Soon after, the semitrailer was removed from the site, but the freeway remains closed between Bulleen Road and the Chandler Highway

Australian Associated Press