This is the shocking moment a pickup truck driven by an alleged drunk man swerved along the road before smashing into an oncoming car.

Motorists behind the reckless driver noticed something is wrong after it is seen swaying between lanes in Chaiyaphum, northeastern Thailand on October 11.

One of the drivers behind, Rungthip, kept on honking his horn to try and catch the attention of the pickup truck driver to stop him.

However, the driver seemed to ignore them despite several near-miss encounters on the highway.

A few moments later, it smashed into an approaching car on the opposite lane after it swayed into the wrong lane again.

The vehicle almost hit a cargo truck which was able to evade it and slammed straight into the red car behind.

Rungthip's dashboard camera was able to film the incident while they were driving at a safe distance behind.

He said: "We knew he was going to cause an accident with the way he was driving. We tried to stop him but it was too late."

The concerned driver immediately called the paramedics who arrived and applied first aid treatment to the injured drivers who were wounded on the arms and head.

The pickup truck driver was detained at the scene and paramedics reportedly confirmed he had been drinking.

The local police also arrived to investigate the scene. They said the drunk man arrested on suspicion of reckless driving charges and damage to property.