Woolmer's death was upgraded to a murder investigation on Friday after a post-mortem examination confirmed that he had died of "manual strangulation".

Police believe the cricket coach may have known his killer or killers, and authorities requested that the entire Pakistan cricket team submit DNA samples and fingerprints to investigators before being allowed to return home from Jamaica yesterday.

Pakistan team manager Talat Ali said his players were "relieved" to go home, and that Woolmer would be missed by the players. "He did a tremendous job for us, " he said.

Yesterday brought further speculation that the coach's death might be connected to his intention to expose a match-fixing scandal in the cricket world.

Former South Africa cricket captain Clive Rice said Woolmer knew a significant amount about the murky world of gambling cartels and that he was convinced it was this knowledge that cost him his life. He said he had "absolutely no doubt" that Woolmer was killed because he knew too much.

This claim has also been made by former Pakistan pacer Sarfraz Nawaz.

The suggestions come as a Pakistani cricket journalist has revealed that Woolmer asked him to help write a book about his experience in charge of the national team.

"I am not a name and shame guy, just the honest facts, " Woolmer wrote in an email to the journalist. "Let the punter make up his own mind etc.

Regardless of the money, the story is worth telling and has to be told in the correct way."

The international governing body of cricket is investigating whether match fixing was a motive for the murder.