BEIJING, Jan. 11 (Xinhua) -- Four key municipal organs of Beijing moved their offices from the downtown area to the eastern suburb of Tongzhou District, the city's sub-center, on Friday.

The four organs are the Beijing Municipal Committee of the Communist Party of China (CPC), the Standing Committee of the Beijing Municipal People's Congress, Beijing Municipal People's Government and the Beijing Municipal Committee of the Chinese People's Political Consultative Conference.

At around 7:36 a.m., a ceremony for raising the national flag was held at a square in the office zone of the sub-center.

Cai Qi, secretary of the CPC Beijing Municipal Committee, said Beijing will strive to turn the sub-center into a model of urban development in the new era and a new landmark for the capital.

Beijing is shifting some of its administrative functions out of the city center into Tongzhou to help address problems including traffic congestion and air pollution. The move is also part of the Beijing-Tianjin-Hebei integrated development plan.

The sub-center aims to accommodate 1.3 million permanent residents by 2035, according a detailed plan for the sub-center's development approved by the central authorities.

More than 240 big projects will kick-start in the sub-center this year, as part of an effort to improve the area in terms of transport, infrastructure, public service and the environment.

Around 75 billion yuan (11 billion U. S. dollars) will be invested into these projects in 2019, according to Beijing Municipal Commission of Development and Reform.