SAO PAULO, March 31 (Xinhua) -- At least 10 people were killed and 21 others injured after a bus carrying workers to their factory jobs in the southern Brazilian state of Parana fell into a ravine Wednesday night, the local Federal Highway Police said Thursday.

According to the police report, the accident occurred before midnight in the municipality of Sapopema, where seven people lost their lives, while the other three died on route to an area hospital.

The bus was carrying over 30 passengers from various regions of the country, who were on their way to a factory owned by Klabin, Brazil's largest paper producer and exporter, in the city of Campos Gerais.

Preliminary information indicated that the driver lost control of the vehicle presumably because of the heavy rains at the time of the accident.