China's former railways minister, Liu Zhijun, has been expelled from the Communist Party of China (CPC) after being found guilty of corruption, the CPC disciplinary watchdog announced on Monday.

Liu, also former Party chief of the Railways Ministry, had been under investigation since February 2011, when he was removed from his position on suspicion of "serious disciplinary violations."

Investigators found Liu used his position to seek huge illegal interests for Ding Yuxin, chairman of Beijing Boyou Investment Management Corporation, maneuvering which caused great economic losses and negative social influence, according to a statement issued by the CPC's Central Commission for Discipline Inspection (CCDI).

The CCDI also discovered Liu, who the statement labeled "morally corrupted," had taken a huge amount of bribes and bore the major responsibility for severe corruption in the railways system.

Liu's behavior seriously violated the CPC's discipline, and the decision to expel him from the Party was made in accordance with the CPC's regulations and approved by the Political Bureau of the CPC Central Committee, the statement explained.

It is suspected that some of Liu's discipline violations may have included criminal acts, so his case will also be turned over to judicial organs, it said, adding that Liu's illegal gains have been confiscated.

The public has long criticized China's railways system as being poorly managed, especially during peak times.

Liu's removal is also believed to be linked to the high-speed train collision last July that killed 40 passengers and injured 172 others, the tragedy having been blamed on improper management.