SEOUL - SOUTH Korean investigators on Thursday blamed lax fire precautions and suspected staff negligence for a karaoke bar blaze that killed eight customers.

A ninth person was seriously injured in the Wednesday evening blaze that gutted the basement bar in the Yongdo district of the southern city of Busan.

'There were no sprinklers in the bar,' Kim Tae-Bong, a firefighter investigating the blaze, told AFP by phone.

'The victims who died became trapped in toxic gas emanating from burning interior finishings and carpets. They were unable to find the way up from the basement amid the toxic, blinding smoke,' he said.

The bodies of five people who had apparently been searching desperately for an exit were found in one room, investigators said.

At the time of the blaze, apparently caused by a power short-circuit, there were 11 people in the bar including two employees who escaped unhurt.

Police quoted by Yonhap news agency said the employees were suspected of fleeing the scene without raising the alarm. -- AFP