The People's Liberation Army (PLA) has started a new round of personnel adjustments among senior military officers ahead of the 18th National Congress of the Communist Party of China.

Two political commissars from local military regions and several generals were promoted, according to reports by the Beijing-based news website Caixin.com on Monday and Tuesday,  citing a military source inside the PLA.

"Those decisions have been announced and implemented inside the army," Chen Baocheng, the author of the reports, told the Global Times.

Zhang Yang, former political commissar in the Guangzhou Military Region, was promoted to the post of director of the PLA General Political Department to take charge of the political affairs of the army, replacing 70-year-old Li Jinai, who was also a member of the Central Military Commission (CMC), according to Caixin.com.

The Hong Kong-based newspaper South China Morning Post (SCMP) reported that Zhang's promotion signaled his likely membership of the CMC, the nation's top military policymaking body.

The paper said that Zhang was promoted largely because of his political reliability, especially after the scandal surrounding former Chongqing Party secretary Bo Xilai, SCMP said.

In addition to accompanying CMC Vice-Chairman Xu Caihou on an inspection tour of several troops in the Guangzhou Military Region in February, after events relating to Bo began to unfold, Zhang published an article in the People's Daily on June 5 calling for absolute obedience to Party leaders during peacetime military operations, reported SCMP.

Former political commissar at the Chengdu Military Region, Tian Xiusi, 62, was promoted to political commissar at the PLA's Air Force. Zhu Fuxi, former director at the Political Department of the Air Force, has now taken Tian's position, according to Caixin.com.

Tian is one of the few senior officers to have real combat experience gained when he was in his 30s, said Chen, referring to the Counterattack against Vietnam in Self-defense (1979-89).

Zhu Fuxi has no real combat experience, but it is not unusual for the PLA to promote those who have been working in political departments to more important positions, said a retired teacher with the Second Artillery Engineering University of the PLA surnamed Song.

"Those who have proven to be politically reliable and performed well in emergency situations will be put into more important positions. And most of the promoted officials have experienced real tests like earthquakes and maintaining national stability at major national events," Song told the Global Times.