The incident was brought to the attention of the third umpire Gamini Silva after television pictures showed close-up shots of Akhtar apparently scratching the quarter seam of the ball.

Akhtar was called for a hearing after an official inquiry by match referee Gundappa Viswanath.

Viswanath, who had requested television evidence after the match, said he would announce his decision at 0630 GMT on Wednesday.

"The umpires advised me to view television clippings, believing that the condition of the ball may have been changed," Viswanath said after the one-hour hearing.

"I will make my decision tomorrow," he added.

Akhtar, who took 3-36 from 9.1 overs, had produced a match-winning spell that saw six New Zealand wickets tumble for 21 runs.

Breaking Law 42.3, which refers to changing the condition of the match ball, is a Level Two offence according to International Cricket Council's code of conduct.

But because Akhtar has been charged with a Level Two offence during the past 12 months, when he threw a bottle into the crowd during Pakistan's tour to Zimbabwe in October 2002, ball tampering would be deemed a Level Three offence.

This would mean a minimum match ban of four one-day internationals and a maximum ban of eight matches.