Suffocating passengers smashed windows on a broken-down train so they were able to breathe.

Locals were crammed into the K1373 locomotive when it was struck by a freight train at Dongxiao Station in Jinhua City, Zhejiang, on July 2, 8:28 pm.

The front carriage derailed, and the collision caused a power outage on the train, disabling the air-conditioning and plunging parts of the carriage into darkness.

As temperatures rose inside, occupants reportedly struggled with the heat.

Dramatic footage shows frustrated commuters, many shirtless, fanning themselves while police tried to calm the situation.

One traveller, Mr Wang, said he boarded the train at Hangzhou South Station at 6:22 pm and was due to arrive in Changsha before 6 am the next morning.

He added: 'The train was stranded for about three hours. There was a power outage, and it was very stuffy inside. I felt like I was about to suffocate.

'The air conditioning stopped, the lights went out, and it became unbearable.'

Mr Wang added that one passenger allegedly broke a window in an attempt to get fresh air. The individual was reportedly taken away following the incident.

After crews replaced the locomotive, the train resumed its journey at approximately 11:27 pm.

No injuries were reported and travellers eventually arrived in Changsha around 9 am the following day.

Officials are now investigating why the cargo train operated by the Jinwen Local Railway Company crashed into the passenger vehicle.