This is the heart-stopping moment a truck smashed into cars when its driver allegedly fell asleep at a junction in Thailand.

Traffic camera footage shows the Isuzu pickup rear-ending a sedan before hitting a motorcycle as it veered out of control in Phayao province on January 10.

The wobbling truck then careened through the intersection and struck a lamppost as it flipped over onto the grass on the roadside.

Police Lieutenant Colonel Peerachet Sawangarrom of the Maeka district police station said the accident happened at around 3:40 pm local time.

Police officers, medics, and rescue volunteers arrived at the scene and found several damaged vehicles and injured locals.

They were identified as Honda City driver Thanakorn Sitthicharoen, 61, Honda Scoopy-i riders Suphanan Kaewmuangpak and Piraya Ohirankul, both 21, and Toyota Hilux Vigo driver Pattanapong Jaimipak, 30.

The motorist who caused the crash was named by officers as Naret Roopaen, 46, who was travelling with passenger Tasanee Deelon, 56.

Naret told police he had been driving from Ayutthaya province and had dozed off at the red traffic light, only to be jolted awake when he crashed into the back of Thanakorn's car. He claimed he tried to steer the wheel to avoid a pile-up.

A street light, several traffic cones and road barriers were damaged in the incident, authorities said.

Police Lieutenant Colonel Peerachet said: 'The truck driver said he did not get enough rest before travelling, which caused him to fall asleep. He will be charged with reckless driving causing injury to others, and causing damage to government property.'

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.

However, a lack of road safety education in schools along with notoriously easy driving tests, police failures to enforce road laws, and chronic under-investment in infrastructure, all appear to hamper the efforts.