ISLAMABAD, Sept. 16 (Xinhua) -- At least 20 people were injured on Sunday when a passenger train derailed in Pakistan's eastern Punjab province, an official of Pakistan Railways said.

A spokesperson of Pakistan Railways said that the incident took place when eight coaches of the Khushal Khan train derailed between Sohan Bridge and Makhad Station in Attock district of Punjab.

Police, security forces and rescue teams rushed to the site and shifted the injured to the District Hospital in Attock.

According to hospital sources, at least four of the injured are in critical condition and being treated in the intensive care unit of the hospital.

The ill-fated train was heading towards the country's northwest city of Peshawar from the southern port city of Karachi.

Following the accident, the railway traffic was suspended on the route and repair work in the track was underway.

A probe into the incident has started to know the reason behind the accident, the spokesperson said.

According to a report presented in Pakistan's Parliament, the country's troubled railway suffered 338 major and minor accidents in four years from 2013 to 2016, in which 118 people lost their lives.

The report revealed that poor tracks, old coaches, non-professional staff and old infrastructure are major reasons behind the accidents.?