A passenger who allegedly tried to open a plane door mid-air was restrained in his seat and arrested.

The flier is said to have sparked panic when he began charging through the aisle of the A320 flying from Taiwan to Thailand on Thursday morning.

Shocked tourists onboard screamed as he allegedly tried to force open the emergency exit while batting away the cabin crew as the plane cruised at 40,000ft.

Onlookers said he was eventually subdued and strapped to his seat for the rest of the four-hour flight.

Footage shows police arresting the suspect when the aircraft operated by flag carrier Thai Air landed at the Suvarnabhumi International Airport in Bangkok at 11:30 am local time.

Yaowarat Pradungchat, one of the passengers on flight TG637 from Taipei, said the drama was the 'scariest thing she has seen on a plane'.

She added: 'This was terrifying. I've been flying for ten years and this is the first time I've encountered something like this.

'There was a Thai passenger who became delirious, trying to open the emergency exit door while we were at cruising altitude.

'Fortunately, there were several heroes who restrained and tied him up. The situation was brought under control.

'It was really scary. This is the first time I've ever encountered such an incident while flying. Thankfully, everyone is safe. '

Police Colonel Chakpong Nuchpadung, the Superintendent of Suvarnabhumi Airport Police Station, said that the suspect was a Thai national. He was taken from the plane and held in custody.

However, the officer said he had been released without charge 'for compassionate reasons'.

The officer added: 'The man's relatives confirmed that he has a history of mental illness and had previously received treatment, though they were unsure if he had missed his medication.

'The Taiwanese company had sent him back to Thailand, citing his mental health condition and his inability to perform his duties. A drug test was conducted, but no substances were found in his system.

'There were no charges filed against the man because Suvarnabhumi International Airport, as the property owner, chose not to pursue legal action. They decided not to press charges, as no harm had occurred and because of their sympathy for the man's mental health condition.'

Under the country's law, any act that endangers the safety of a vehicle or its passengers carries a penalty of imprisonment from six months to seven years as well as fines.

While the Air Navigation Act states that a passenger who 'violates or fails to comply with the instructions of the aircraft's captain or crew can face imprisonment for up to one year'.