The sport's chiefs have vowed to get tough with fans after Stephen Hendry was distracted at a crucial time during play on Friday.

Hendry was on his way to a 147 break in Sheffield during the 17th frame of his semi-final against reigning champion Ronnie O'Sullivan.

Warning

But he twice withdrew from his shot after phones rang in the audience.

It prompted a stern warning from referee Eirian Williams to the 900 spectators.

Hendry's hopes of maximum ended when he was on 113 after he missed the 15th black.

It was the same stage at which he had failed in his quarter-final with Ken Doherty when the 147 had appeared at his mercy.

After the frame World Snooker official Mike Ganley entered the auditorium and warned spectators who allowed their phones to ring that they would be ejected.

Interruptions

He repeated his warning after the session which ended 12-12.

"Due to the interruptions in play on Friday night, we will be clamping down on similar incidents in future," said Ganley.

"Anyone who leaves their phone on during play, and then it goes off, will be asked to leave the auditorium immediately.

"You can't say how a break will finish but it is important to give the players the best opportunity without having to contend with things like mobile phones.

"We know it is not practical to search people and prevent them from taking phones into the auditorium but we will ask them to use common sense for the good of everybody."