BEIJING, Jan. 1 -- The Chinese central government shows grave concern over the break-in at the headquarters of the People's Liberation Army (PLA) Garrison in Hong Kong, a spokesman said on Wednesday.

Several local residents forced their way into the PLA Garrison headquarters at Hong Kong Central last Thursday afternoon, defying the warning of the guard on duty. Two of them were detained by Hong Kong police on Wednesday.

The PLA garrison troops, who perform defense duties in Hong Kong according to law, are a symbol of national sovereignty, the spokesman from the Hong Kong and Macao Affairs Office of the State Council said in an interview with Xinhua.

All PLA garrison barracks in Hong Kong are protected by law. Those who disregarded the law and forced into the barrack should be punished, the spokesman said.