Five people including a pregnant woman were killed and six others were injured when a pickup truck hit an ambulance in Thailand.

The vehicle reportedly skidded on the rain-drenched road, smashing into the Phrao Hospital ambulance transporting a woman in labour in Chiang Mai province on May 9.

Police said they were notified of the accident at 5:30 pm.

A spokesman said: 'The ambulance from Phrao Hospital was transporting a pregnant woman to Sansai Hospital. 

'However, due to the slippery road caused by the rain, the black Isuzu pickup truck lost control and collided with it, resulting in five deaths and six injuries. 

'According to the preliminary investigation, the ambulance was travelling at a speed of only 67 kph. Forensic police are inspecting the scene and gathering evidence.'

The ambulance driver was severely injured and extracted by rescuers from his seat using metal cutters. The ambulance nurse suffered a deformed leg from the crash.

The deceased were identified in reports as the pregnant woman Phusanisa Gomin, 26, her unborn child, pickup truck driver Yongyuth Saensri, 51, Yongyuth's wife Daorueng Saensri, 46, and a pickup truck passenger Sunee Pinngern, 54.

The six injured were recovering at the Sansai Hospital, Phrao Hospital, and Nakornping Hospital.

The accident is the second this year involving a Phrao Hospital ambulance. 

On January 16, another medical vehicle from the same hospital crashed into a parked truck on the side of a road, killing two people.

Despite being one of the wealthiest countries in Asia, Thailand suffers from chronic underinvestment in its highways and education, contributing to its poor road safety levels. Only a handful of African countries are worse.

Thailand has one of the world's worst road safety records. Ministers have set the goal of reducing fatalities from 32.7 deaths per 100,000 people to 12 per 100,000 people by the year 2027.