"It seems difficult to believe at this stage that it was a complete stranger," the deputy police commissioner in Kingston Mark Shields said in an interview with BBC Radio Live.
"It is imperative that we keep an open mind, but I have to say at this stage it looks as if it may be somebody somehow linked to him, because clearly he let somebody into his hotel room and it may be that he knew who that person was."
Shields said that police were probing video recordings from the hotel's closed circuit television cameras but had not yet found anything suspicious.
Shields also "unequivocally dismissed" rumours that arrests had been made. "That's nonsense, as far as I'm concerned. There's actually no truth in that," he said.
In a press conference Thursday, Jamaican police spokesman Karl Angell confirmed Woolmer had been the victim of foul play.
"The pathologist report states that Mr. Woolmer's death was due to asphyxia as a result of manual strangulation," Angell said.
"In these circumstances, the matter of Mr. Robert Woolmer's death is now being treated by the Jamaica police as a case of murder."
Woolmer was declared dead in hospital Sunday after being found unconscious in his room. He was 58.
"I don't want to talk about suspects at this stage," Shields said Thursday.
He suggested more than one person may have been involved because he was a large man and difficult to subdue.