Apple Inc. on Wednesday removed from its app store an app that protesters in Hong Kong have used to track police movements, saying it violated rules because it was used to ambush police.

The U.S. tech giant had come under fire from China over the app, with the Chinese Communist Party’s official newspaper calling the app “poisonous” and decrying what it said was Apple’s complicity in helping the protesters.

Apple had only just last week approved the HKmap.live app, which crowdsources the locations of both police and protesters, after rejecting it earlier in the month.

Apple said in a statement that it had begun an immediate investigation after “many concerned customers in Hong Kong” contacted the company about the app and Apple found it had endangered law enforcement and residents.

“The app displays police locations and we have verified with the Hong Kong Cybersecurity and Technology Crime Bureau that the app has been used to target and ambush police, threaten public safety, and criminals have used it to victimize residents in areas where they know there is no law enforcement,” the statement said. Apple did not comment beyond its statement.

The company also removed BackupHK, a separate app that served as mirror of the main HKlive.map app.

On a Twitter, an account believed to be owned by the HKlive.map app’s developer said it disagreed with Apple’s decision and there was no evidence to support the Hong Kong police’s claims that the app had been used in ambushes.

The app consolidated content from public posts on social networks, the developer said, and moderators would delete content that solicited criminal activity and would ban repeated attempts to post such content in the app.

“The majority of user review in App Store … suggest HKmap IMPROVED public safety, not the opposite,” it added.

Apple also removed the Quartz news app from its app store in China because Chinese authorities said the app violated local laws.

Quartz Chief Exeuctive Zach Seward told technology publication The Verge in a statement: “We abhor this kind of government censorship of the internet, and have great coverage of how to get around such bans around the world.”

The HKlive.map app was removed from Apple’s app store globally but continued to work for users who had previously downloaded it in Hong Kong, Reuters found. A web version was also still viewable on iPhones.

On Tuesday, the People’s Daily said Apple did not have a sense of right and wrong, and ignored the truth. Making the app available on Apple’s Hong Kong app store at this time was “opening the door” to violent protesters in the former British colony, the newspaper wrote.

Under Apple’s rules and policies, apps that meet its standards to appear in the app store have sometimes been removed after their release if they were found to facilitate illegal activity or threaten public safety.