BRASILIA, Feb. 3 (Xinhua) -- At least 15 people were killed when a bus carrying about 60 people overturned early Tuesday on a stretch of a state highway in western Alagoas state in northeastern Brazil, authorities said.

The incident occurred in the municipality of Sao Jose da Tapera as the bus was returning from Ceara to Alagoas, according to the Alagoas state government.

Preliminary information indicated that the victims included seven women, five men and three children. The injured were taken to hospitals in the region for treatment.

Witnesses said the driver lost control of the vehicle before it veered off the road. The Civil Police have launched an investigation into the cause of the accident.

Alagoas Governor Paulo Dantas declared three days of mourning. ■