Thirteen persons were killed and over 50 seriously injured on Thursday when a bus overturned and rolled down a hill at Tuilaphai area in Manipur's Churachandpur district, official reports said.

Earlier, the reports had said that 22 people were killed and 30 injured in the accident.

Explaining the revision of the death toll, officials said that some of the seriously injured were earlier taken to be dead.

The seriously injured were admitted to the Regional Institute of Medical Sciences and Hospital in Imphal.

The bus was coming from Tuilaphai in Henglep sub-division to Churachandpur when the accident occurred at 7.30 am at a spot about 60 km from Imphal, the reports said.    

The bus is yet to be retrieved.