Death toll has risen to 11 in an explosion which erupted following a road accident involving a tanker in Nigeria's southwestern state of Osun, the local road safety police said on Tuesday.

Anthony Oko, a road safety police commander, confirmed to reporters that one of the two injured casualties had died while receiving treatment at a government health facility.

An 18-seater Toyota Hiace bus on a road trip from a neighboring state had rammed into a moving tanker near Ife Town, in Osun State on Sunday. This caused the content of the tanker to spill over, causing the explosion.

Ten people were earlier reported to have died on the spot.

It was a lateral crash involving all 12 passengers in the 18-seater bus.

The road safety police said investigation indicated that the accident was caused by "impatience and excessive speeding by the driver of the commuter bus and a wrong U-turn drive by the truck driver."

source: xinhua