Subang. At least 11 people were killed after a bus carrying dozens of vocational school students overturned in Subang regency, West Java, on Saturday evening.

A local hospital reported that 20 people are being treated for injuries, some of whom are in serious condition.

Reports indicate that the bus was transporting 40 students from Lingga Kencana Vocational School in Depok, West Java.

The identities of the victims have not yet been disclosed.

"The death toll from this accident is 11, including six women and five,” West Java Police Chief Insp. Gen. Ahmad Wiyagus said.

He couldn’t immediately confirm if the deceased were all the bus passengers pending the ongoing investigation.

The bus was traveling north in the hilly area of Ciater when it veered off the lane on a steep slope and collided with another car coming from the opposite direction, according to Subang Police spokesman Adjunct Comr. Yusman, as reported by the Kompas news website.

The collision, which occurred around 6:45 p.m., caused the bus to overturn onto its right side. It continued to slide down the slope and collided with three motorcycles parked on the roadside before finally coming to a stop after hitting an electricity pole.

Police have stated that the bus belongs to the bus operator Trans Putera Fajar.

According to the director of Subang Municipal Hospital, Ahmad Nasuhi, the hospital received at least nine bodies from the accident.

Injured passengers were transported to several other hospitals in the regency for emergency treatment.

Note: The story has been updated with remarks from the West Java Police chief.