BEIJING (Reuters) - Two top officials previously in charge of China’s official state lottery have been stripped of their positions on suspicion of taking bribes, China’s top graft watchdog said late on Sunday.

Since assuming power in late 2012, President Xi Jinping has pursued a relentless campaign against corruption, warning that the problem could threaten the party’s ability to retain power if left unchecked.

Former head of the China Welfare Lottery Management Center, Bao Xuequan, and his former deputy, Wang Yunge, were suspected of corruption following an investigation by the Central Commission for Discipline Inspection (CCDI), China’s top graft watchdog.

The Ministry of Civil Affairs, which runs the Welfare Lottery, had removed both officials of their party and state positions, the watchdog said in a statement on its website.

Bao was found to have used his position to seek material benefits, accept gifts and have “improper sexual relations,” while Wang was found guilty of the same crimes, as well as for resisting the investigation against him and on suspicion of leaking state secrets, the CCDI said.

Wang and Bao could not be reached for comment. Both their cases will be handled by the judicial authorities, the watchdog said. Officials charged with crimes by the CCDI are almost always found guilty.

Two civil affairs officials in charge of oversight of the lottery were demoted in February this year for failing to do enough to tackle “systematic corruption” in the ministry.

Gambling is officially illegal in China, outside of the two state-run lotteries, the China Welfare Lottery and the China Sports Lottery.

Earnings from the lotteries are supposed to be funneled back into social welfare and sporting projects, though it has long been suspected that a portion of the profits are pocketed by corrupt officials.

A 2015 report from the Chinese Academy of Social Sciences, a state-backed think tank, found that almost 17 billion yuan ($2.56 billion) was improperly used out of a randomly inspected 658 billion yuan spent from the state lottery fund that year.