A man has been arrested for calling in two false bomb threats on the subway system, police said Thursday.

The suspect, surnamed Yang, 41, called the police emergency line around 3 pm Saturday and told the operator that his friend, a man surnamed Yang, planned to set off a bomb on metro Line 2, according to a press release from the Shanghai Public Security Bureau.

Yang said that his friend intended to buy explosives for the attack. He did not tell police where he was calling from.

The city's metro police division began investigating the threat.

Yang again called the police around 8 am Monday on his cell phone. Police tracked him down and found him passed out drunk on the floor inside Century Avenue Station around 10:30 am. He was not carrying any dangerous items at the time.

Police determined that Yang was referring to himself when he called in the threats.

He told police that he had been seriously injured in February 2012 when he fell down the stairs at Century Avenue Station after drinking too much.

He repeatedly demanded compensation from the metro's operator, but was always refused. The bomb threats were his way of getting back at the company.

Police have detained Yang for "fabricating and spreading false terrorist information," the press release said.

Police have established an effective mechanism for dealing with false bomb threats and strictly enforce the law against people who spread false terrorism information against the public, according to the press release.