YAOUNDE: At least 40 people died and dozens were injured in Cameroon on Wednesday and Thursday in three bus crashes, the transport ministry said, warning it will punish any companies involved in further incidents.

Twenty-two of the deaths occurred on Thursday morning when a bus collided with a lorry carrying sand north of the capital Yaounde, the minister, Jean Ernest Massena Ngalle Bibehe, said in a statement.

On Wednesday night, 16 people died and several were injured after a collision between another passenger bus and a semi-trailer truck about 50 kilometres east of Yaounde.

Finally, a third accident left two dead and 28 injured in the center of the country.

The crashes come as the government conducts a public information campaign to improve road safety in the country, Bibehe said, criticising the negligence of transport companies ferrying people and goods between cities.

The minister warned bus operators and cargo hauliers that "he will proceed from now on to suspend all their transport activity in the event any new involvement in a road accident".

Road accidents involving buses are relatively frequent and deadly in Cameroon.

At least 53 people died at the end of January when a bus collided with a van carrying fuel, while just a month earlier, at least 37 people, including 10 women and four children, died in another accident.