An air echelon escorting flags flies over Tian'anmen Square during the celebrations marking the 70th anniversary of the founding of the People's Republic of China (PRC), in Beijing, capital of China, Oct. 1, 2019. (Xinhua/Liu Xiao) 

An air echelon flew over Tian'anmen Square Tuesday morning escorting flags of the Communist Party of China (CPC), the nation, and the People's Liberation Army (PLA), marking the start of a grand National Day military parade.

Each flag was carried by a Z-8B transport helicopter and guarded by two Z-10 armed helicopters on both sides.

Eight Z-10 armed helicopters and 12 Z-19 armed helicopters followed in a formation that spelt "70" in the air.

On the ground, a formation of Guard of Honor marched along the east Chang'an Avenue to Tian'anmen Square, holding high the CPC flag, the national flag and the PLA flag.

With an active force of around 2 million, the PLA has come a long way since its birth -- the armed uprising by 20,000 soldiers in the city of Nanchang on Aug. 1, 1927.