The violent attacks over the weekend in Hong Kong against the central government institution have challenged the principle of "one country, two systems" and are intolerable, the Ministry of National Defense said on Wednesday.

Speaking in Beijing, ministry spokesman Wu Qian said authorities have been following the situation in the Hong Kong Special Administrative Region closely and are paying particular attention to the siege of the Liaison Office of the Central People's Government in the Hong Kong SAR－the central government's top representative institution in the city－that rapidly turned violent on Sunday.

The protests have challenged the central government's authority, the bottom line of the "one country, two systems" principle, and the actions are "absolutely intolerable", Wu said.

Hong Kong, as the Pearl of the Orient, cannot be tainted, Wu said at the news conference.

When asked whether the People's Liberation Army will be deployed to the SAR to pacify the city's chaos, Wu referenced the Law of the People's Republic of China on the Garrisoning of the Hong Kong Special Administrative Region.

According to Article 14, pursuant to the provisions of the Basic Law of the Hong Kong SAR, the SAR government may, when necessary, ask the central government for assistance from the PLA Hong Kong Garrison in the maintenance of public order or in disaster relief.

The PLA Hong Kong Garrison has powers as stated in the laws of the HKSAR when rendering assistance.

The law of the PRC on the Garrisoning of the HKSAR stipulates that troops immediately return to their station upon completion of tasks.

Since mid-June, Hong Kong has seen a series of protests against the now-suspended extradition bill. They often turn violent later in the night, and the extent of violence has been escalating recently.

The latest event involved vandalism of the Liaison Office on Sunday in which the national emblem was defaced.