LONDON (AP) — A British travel company says four Britons on pilgrimage in Saudi Arabia have been killed in a bus crash.

Hashim Travel said the four were among 18 people on a bus travelling from Mecca to Medina on Saturday. The travel company says the bus collided with a gasoline tanker truck. It says other people on the bus were treated for injuries.

The Foreign Office called the collision near the town of Al Khalas in west Saudi Arabia a "serious road traffic accident." It said in a statement it is working to assist families of the people killed and injured. It didn't give further details.

Hashim Travel says it has organized pilgrimage tours for more than 15 years.