Jamaica's investigating authorities collected DNA samples from Pakistani cricketers on Friday.

Pakistan's cricket coach Woolmer was murdered in his hotel room on Sunday, throwing cricket into turmoil and casting a shadow on the ongoing World Cup.

The police said on Thursday that as per the post-mortem report, Woolmer died due to asphyxia caused by manual strangulation.

Since there was no evidence of break-in, it is believed that Woolmer, 58, must have known the killer.

Given Woolmer's build, more than one might be involved, the police added.

Jamaican police have also sought help from the Scotland Yard in the investigation, suggesting the leads spread across international borders and a possible involvement of the betting mafia.

The Pakistani players had earlier been questioned and fingerprinted.

DCP Mark Shields, however, said there has been no suspects identified in the case so far and the visiting team was free to leave the country.

The team had left for Montego Bay on Thursday.

In Islamabad, Pakistan Cricket Board's outgoing chairman Nasim Ashraf said the players were awaiting confirmation of flight bookings and were expected fly out of the Caribbean later Saturday.