BEIJING - THE death toll from a subway tunnel collapse in eastern China rose to eight on Tuesday as searchers battled through a sea of mud in an effort to locate 13 other missing people, state press said.

Rescuers found one more body on Tuesday, three days after an accident at a construction site for a subway in Hangzhou city trapped 21 labourers, the China News Service said.

Seven people had been reported dead on Monday.

Altogether 75 metres of the tunnel collapsed on Saturday, creating a huge crater that also trapped 11 vehicles, including at least one bus, it said.

Most of the water was pumped out of the crater on Monday, but mounds of mud remained at the bottom of the tunnel, according to Chinese press reports.

Officials on Sunday said the chances of survival of those unaccounted for were slim.

Hangzhou, a scenic city near Shanghai, started construction of a major subway network in March last year. -- AFP