At least 21 garment workers were killed when a speeding truck hit their van on Tuesday in eastern Cambodia, a local newspaper reported. The incident reportedly also left about two dozen people injured.

Authorities reportedly said that the workers were traveling to their factory in eastern Svay Rieng province, about 80 miles east of Phnom Penh near the border with Vietnam. The bus, which was carrying tourists from Vietnam and other passengers, hit the van while trying to pass a car, Chieng Am, a provincial governor said, adding that no one on the bus was hurt, according to the Associated Press (AP). The death toll from the accident is expected to rise.

“Twenty-one people died when a van filled with workers crashed into a tourist bus traveling from Vietnam to Phnom Penh,” Svay Rieng provincial police chief Koeng Khorn said, the Cambodia Daily reported.

Pav Sina, president of the Collective Union of Movement of Workers, said the workers were members of his union and at least five of them remained in serious condition, according to the Cambodia Daily.

“Five victims are now receiving urgent medical treatment at Chi Phu referral hospital in Bavet City,” he reportedly said. “We have no hope the five victims will survive because of their serious condition.”

Officials reportedly said that the overcrowded van was driving within the speed limit. Every year road accidents lead to several deaths in Cambodia. Over 2,000 people were killed in road accidents last year, AP reported, citing the country's transport ministry.