Mike Tyson's reinstatement hearing has been postponed from Saturday after the results of psychological tests on the troubled boxer failed to arrive in Las Vegas before a deadline.

The Nevada State Athletic Commission has not set a new date for the hearing there, officials said. The five-man panel stripped Tyson of his boxing licence last year after he bit Evander Holyfield twice in their world heavyweight title fight on June 28th, 1997.

Ten days ago, the commission decided Tyson must undergo psychiatric testing before they would decide on his fitness to return to the ring.

Tyson underwent a series of psychological tests at Massachusetts General Hospital in Boston from Wednesday through last Sunday.

But doctors did not had time to assemble to findings and deliver them to the commission by a Monday afternoon deadline.

A letter from physician Ron Schouten to Elias Ghanem, the commission chairman, said the reports would be ready today and were delayed due to the "length of evaluation process (and) the scoring on the psychological and neuro-psychological testing".

Ghanem had also wanted more information about Tyson's scuffle with two men after a Maryland traffic accident. A hearing on that matter has been scheduled for Friday.