A group of over 350 Hong Kong civil servants wrote a petition to the government on Thursday that said they are “absolutely disgusted” by the excessive use of police force against demonstrators, and warning they might call a strike if the abuse continues.

“We have lost count of the number of ‘crimes against humanity’ Hong Kong police committed and we feel ashamed to call them colleagues,” the petition said, citing the concerns expressed by the United Nations Human Rights Commission.

“If the government refuses to make any concession, it will disappoint civil servants and leave little room for dialogue. We cannot preclude some colleagues making their voices heard by taking part in marches, rallies, or strikes, to save Hong Kong from the brink of breakdown,” it warned.

The South China Morning Post reported the petitioners criticized Hong Kong Chief Executive Carrie Lam for “turning a blind eye to public demand” and insulting young demonstrators as anarchists with “no stake in society.” They rejected warnings by civil service secretary Joshua Law Chi-kong that government employees who rally with the protesters or go on strike could face serious penalties. Hong Kong’s Civil Service Bureau also urged government employees to remain “professional” and avoid going on strike.

The petition was anonymous, but the participants attached photos of their staff ID cards with the names obscured to show they were government employees. Some of the signatories were willing to identify themselves and talk to the media, such as police administrative employee Tina Lee, who said she was disturbed by the police “firing tear gas in a railway station, pushing protesters down escalators and shooting them in the head.”

Lee added that she did not want to go on strike because it would have little effect and the city government might “hire newbies at lower pay” to replace strikers.

“Petitions were launched by elite administrative officers, executive officers, government lawyers and doctors in public hospitals, while civil servants also staged an unprecedented rally,” the South China Morning Post noted on Thursday. A previous petition filed by a smaller group of civil servants demanded an independent investigation of police brutality.

Civil servants joined a citywide strike last week, the first general strike in Hong Kong in over 50 years. Much of the city was paralyzed by the mass demonstration. The new petition from civil servants would appear to be threatening larger and longer action if its complaints are not addressed.