Law enforcement officers found almost 100 million yuan ($16 million) cash in the home of a senior official of the National Energy Administration who was investigated recently, caixin.com reported on Thursday.

The officers found the huge amount of crash when they took Wei Pengyuan, a deputy director of the Coal Department at the National Energy Administration, from his home for investigation.

They borrowed 16 currency counting machines from a Beijing bank to count the money, and four broke while working, possibly because of the heavy workload, the report said.

A source was quoted as saying that Wei may be investigated for problems in approving coal mine reconstruction and infrastructure construction projects, which he oversees for the administration.

According to public information, at least four reconstruction or construction projects were approved by the National Development and Reform Commission and the National Energy Administration since 2013.

Wei became deputy director of the National Energy Administration in 2008 when the administration was established. He was last seen participating in public activities on Jan 9, 2014, when he visited a coal mine in Shandong province.

Another administration official under investigation recently is Hao Weiping, director of the electricity department. Hao, who was investigated early last month, was also promoted to his post in 2008.

Wei said in September 2011 that the joint management of coal and electric power would be carried out as a long-term policy and be given preferential support in project approval.

However, it is not yet known if the investigations of the two are related.

The investigations come as the Central Committee of Communist Party of China intensifies its anti-corruption efforts to include the energy sector.

The CPC has already set its sights on the State-owned energy sector, including State Grid Corp of China and China National Petroleum Corp.

In March, the chairman and the president of Three Gorges Corp stepped down, but none have yet been accused of any wrongdoing.