Gunmen in Burkina Faso killed at least 37 people on Wednesday in an attack on a convoy carrying employees, suppliers and contractors of a Canadian mining company, one of the deadliest episodes in a recent tide of violence that has gripped the West African nation.

The mining company, Semafo, which is based in Montreal, said that five buses escorted by Burkina Faso’s military were attacked while traveling to the Boungou mine, an open-pit gold mine in the eastern part of the country. They were on their way from the city of Fada-Ngourma, about 25 miles away.

Lt. Col. Saïdou T.P. Sanou, the governor of the country’s eastern region, confirmed the death toll in a statement and said that another 60 people had been wounded, but he offered no information about the victims’ identities.