The military's anti-corruption officials and prosecutors arrived in Puyang in February 2012, sources close to the situation said. One month later, officials from the party's anti-corruption watchdog and the country's top prosecutor's office joined the investigation.
Gu stepped down from his post in May 2012.
Colonel Gong Fangbin, a professor at the PLA National Defense University, the military's top institution for higher learning, told state media on August 1 that Gu was involved in corruption cases.
Public documents show that Gu was born in 1956 in Dongbaicang village. However, people close to his family said he was born in 1954.
Gu was recruited by the military in 1971 after he graduated from junior high school. He later worked in the air force in the northeastern province of Jilin.
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In 1985, Gu was transferred to Puyang, where he became involved in the business operations of the local military department. A decade later he was promoted to head the military's logistics department for the Puyang area.
Gu was promoted to the Jinan Military Region in 1994 and was again in charge of logistics. The military region is one of seven in the country and covers a central and eastern portion of China.
He was named the deputy head of the infrastructure department of the PLA General Logistics Department in Beijing in July 2001. Two years later he was promoted to major general.
Gu became the deputy chief of the PLA General Logistics Department in 2009, and in 2011 he was promoted to lieutenant general.