Twelve Indians, working in a construction company in Bhutan, were killed and six others injured when a boulder hit the rear end of the truck they were travelling in, police said.

The incident occurred when the truck was negotiating a narrow wet stretch of road while returning from their work site near Tala Dam at Wangkha in Chukha district at around 8.30 pm on Saturday.

Police said 10 workers died on the spot with their bodies found smashed and scattered beyond recognition.

Two died after reaching the Tsimasham hospital. Of the six injured, the condition of three is critical and have been shifted to Thimphu referral hospital.

The truck belonged to Hindustan Construction Company (HCC). The bodies have been handed over to Tala project manager S K Sarkar.