An ambulance carrying a woman in labour pain to the North Bengal Medical College and Hospital in Siliguri collided head with a truck at Naukaghat near here on Thursday early morning, killing the patient and two others and injuring her husband.

The deceased were Anisha Rai, 18, and Lila Rai, 55, who was accompanying the pregnant woman, and ambulance driver Abhishek Biswakarma, 30.

Anisha’s husband Kapil has been admitted to the NBMCH with serious injuries.

According to police sources, Anisha was supposed to deliver her child in Kalimpong. But as her condition deteriorated, doctors referred her to the NBMCH.

After the accident, police extricated the four persons from the mangled remains of the ambulance and took them to the NBMCH where doctors pronounced three of them dead.

“The killer truck somehow escaped. Searches are on to trace the vehicle and the driver,” said a police officer.