A 27-year-old Iranian man has been identified as the victim of a pre-dawn street assault Sunday in central Nagoya, in which he was stabbed and bashed by several Persian-speaking men before dying of blood loss in hospital six hours later, police said Wednesday.

The victim, named by police as Anami Shirmard Milad, is believed to have illegally entered Japan, the police added, as no reference to his name can be found in immigration records. Police suspect, based on collected evidence, that the violent attack is related to drug smuggling.

The man was attacked with knives and metal bats in the driver's seat of his car around 1:30 a.m. Sunday by a group of five or six masked men. The assailants, who had used two cars to force the victim to pull over, then fled in a third car that arrived from behind.

Video footage taken by a resident of the neighborhood about 2 km southeast of JR Nagoya Station shows the attackers shouting in Persian before leaving the scene, and then returning five minutes later with one looking inside the victim's car, according to the police.

A black pouch containing about 40 unused syringes was found in the grass on a nearby median strip, with the footage showing something black being thrown away, suggesting the victim did so when he was attacked.

The getaway vehicle, displaying a license plate of neighboring Mie Prefecture, has been found within Nagoya. All three cars used by the attackers have apparently been repeatedly resold without being registered by new owners, making it difficult to track them, the police said.