Top Chinese military leaders Zhang Youxia and Liu Zhenli have been placed under investigation for suspected “serious” disciplinary violations, according to the Ministry of National Defence.

Zhang is the first-ranked vice-chairman of the Central Military Commission (CMC), China’s top military command body headed by President Xi Jinping, while Liu is chief of its Joint Staff Department.

Zhang’s position as CMC No 2 after Xi makes him the highest-ranking uniformed officer in the Chinese military.

Zhang and Liu were “suspected of serious violations of discipline and law”, the defence ministry said in a short announcement on Saturday.

“After deliberation by the CPC Central Committee, it was decided to initiate an investigation into Zhang Youxia and Liu Zhenli,” a ministry spokesman said, referring to the Communist Party’s highest decision-making body.

Zhang is also a member of the 24-man Politburo, the party’s centre of power.