After a weekend of brutal crackdowns by police, Chinese Communist authorities are accusing pro-democracy demonstrators in Hong Kong of engaging in “terrorism” and are threatening to militarily invade the city.

A small number of protesters threw petrol bombs at police on Monday, prompting Chinese authorities to attributing the terrorism charges to the vast majority of demonstrators who are protesting police brutality.

Yang Guang, spokesman for China’s Hong Kong and Macao Affairs Office warns the Chinese government will stamp out protesters mercilessly.

 “Such violent crimes must be dealt with resolutely and in accordance with the law, without mercy,” Guang said in remarks translated by state-run media.

“If we allow these types of terrorist activities to continue, then Hong Kong will slide into a bottomless abyss,” China’s liaison office in Hong Kong added Monday.

China’s military vehicles reportedly passed through the Customs facility in Shenzhen, China on Monday en route to Hong Kong. 

Since June, Hong Kong has been besieged by mass protests calling for democratic reforms and an independent investigation into police conduct.

The demonstrations began over opposition to an extradition bill that would have let people be sent to mainland China to face trial. Protesters demanded the law be scrapped immediately.

The government has since suspended the bill. However, the protests have evolved into a much broader backlash against the city government and its political masters in Beijing, emerging as the biggest popular challenge to Chinese leader Xi Jinping since he came to power in 2012.  

Demonstrators are now demanding democratic reforms, including the dissolution of the legislature, a probe into alleged police brutality and are demanding the resignation of the city’s leader, Carrie Lam.  

Both the demonstrators and police have resorted to more extreme tactics.

Hong Kong’s airport cancelled all flights Monday, after thousands of protestors rallied in the main terminal to denounce violence.

“Airport operations at Hong Kong International Airport have been seriously disrupted … all flights have been canceled,” the city’s airport authority said in a statement. “All passengers are advised to leave the terminal buildings as soon as possible.”

Police on Monday morning showcased water cannons that they plan to employ during future demonstrations.

Amnesty International’s Hong Kong director Man-Kei Tam blasted the Chinese government for threatening its people with the dangerous weaponry.

“Water cannons are not a toy for the Hong Kong police to deploy as a sign of strength.” Tam said. “These are powerful weapons that are inherently indiscriminate and have the potential of causing serious injury and even death.

Demonstrators are demanding an independent probe into the handling of the protests.