BEIJING - China will impose even tougher security measures for the 60th anniversary of the founding of the People's Republic in October than it did for last year's Olympic Games, state media said Wednesday.

Thousands of elite police and soldiers are staging drills this week to prepare for a range of scenarios, with teams defusing a mock low-grade nuclear bomb and preventing a chemical plant explosion, the China Daily reported.

The "Great Wall" security exercises ahead of National Day on October 1 cover a large swathe of northern China, from Inner Mongolia north and west of Beijing to Hebei province which surrounds the capital, it said.

"The scale of the operations shows that the security level for the October 1 event will be even higher than the Games last summer," the paper said.

Anti-terrorism forces are also rehearsing responses to simulated bombings, hijackings and street shootings, the report said.

Nearly 100,000 commandos, police and army troops were deployed to ensure security during the Beijing Olympics in August - a mobilisation that sometimes made it difficult for fans to get in and out of event venues.

Authorities are concerned about possible action by Muslim extremists from China's western-most Xinjiang region, the report said, adding that an as-yet unexplained deadly bus fire in southwest Chengdu has also raised alarm.