BEIJING -- Chinese President Xi Jinping is reshuffling the military's leadership to add more loyalists to the top ranks, seeking to consolidate his authority going into this fall's national congress of the Communist Party.

Military insiders say final discussions are underway on doubling to four the number of vice chairmen of the Central Military Commission -- the country's top uniformed officers. The change is likely aimed at reducing the authority held by any one of the second-tier officials, putting more power in the hands of Xi, who chairs the body.

Of the current vice chairmen, Gen. Xu Qiliang, a driving force behind Xi's push to modernize the military, is to stay on. The other -- Gen. Fan Changlong, who is close to Xi's predecessor Hu Jintao -- is set to step down at the upcoming congress. The plan is to replace him with Gen. Zhang Youxia, director of the military's General Armaments Department, whose father served in the same unit as Xi's father.

Gen. Wei Fenghe, commander of the army's Rocket Force, is the leading candidate to fill one of the new posts. Wei was the only officer promoted to general just after Xi took the helm of the party and the military commission in November 2012.

It has been rumored that the other spot could go to Gen. Li Zuocheng, only recently tapped to lead the military's Joint Staff Department. Li has shot up through the ranks under Xi, reportedly as a reward for loyalty. The number of vice chairmen could also be set at three rather than four, according to a military source familiar with the situation.

The appointments will be solidified as early as the Communist Party's Central Committee plenary session scheduled for Oct. 11, a week before the twice-a-decade party congress.

As for the rest of the 11-member Central Military Commission, Gen. Fang Fenghui, Li's predecessor as head of the Joint Staff Department, and General Political Department chief Gen. Zhang Yang were reportedly arrested in late August on suspicion of "disciplinary violations." The allegations are believed to involve graft, though details have not been disclosed.

Though such arrests are extremely unusual, the two officers are not the only Central Military Commission members ensnared in Xi's anti-corruption campaign. Guo Boxiong and Xu Caihou, both loyal to former President Jiang Zemin, were previously ousted over bribery allegations. Fang and Zhang reportedly had close ties to Guo and Xu, respectively.

China has also appointed new leaders for armed-forces branches, according to local media. The new army and air force leaders, Han Weiguo and Ding Laihang, are widely believed to be close to Xi, having served in Fujian Province, where the president spent much of his career. Shen Jinlong, who became navy chief in January, has also been picked for key posts under Xi.