A senior Chinese civil aviation official who committed suicide last week had been suffering from insomnia and probably depression also, a source close to the aviation industry revealed Tuesday.

The official, Liu Yajun, chief of Central and Southern Regional Administration (CSRA) of Civil Aviation Administration of China, threw himself in front of an oncoming train Thursday afternoon, according to sources with Guangzhou-based China Southern Airlines and Baiyun Airport.

According to a note he left and accounts from family members and colleagues, Liu was suffering from long-term insomnia and lack of rest.

He was also most probably suffering from depression, according the source.

Liu sometimes wept alone at home after coming to work in Guangzhou where work pressure was heavy, the source said.

Books on curing insomnia and psychological problems were found in Liu's office. The family said he often searched online for such information.

Liu, around 50, took office as chief of the CSRA in February, 2009.

There was no evidence he'd been involved in corruption, the source said.

A funeral service was held for Liu on Monday morning.