SAN FRANCISCO (REUTERS) - Apple Inc on Wednesday (Oct 9) removed an app that protesters in Hong Kong have used to track police movements, saying the app violated its rules because it was used to ambush police and by criminals who used it to victimise residents in areas with no law enforcement.

The US 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 Hong Kong protesters.

Apple rejected the crowdsourcing app, HKmap.live, earlier this month but then reversed course last week, allowing the app to appear on its App Store.

Apple said in a statement that it has began an immediate investigation after "many concerned customers in Hong Kong" contacted the company about the mapping app.

"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 victimise 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. Hong Kong police had no immediate comment.

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 and that moderators would delete content that solicited criminal activity and would ban repeated attempts to post such content in the app, it said.

"The majority of user review(s) in App Store ... suggest HKmap IMPROVED public safety, not the opposite," it added.

In a separate move, 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."

ANGER IN HONG KONG

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.

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.

In 2011, Apple modified its app store to remove apps that listed locations for drunken driving checkpoints not previously published by law enforcement officials.

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.

Word of the HKmap.live app's removal spread quickly in Hong Kong.

"Does the entire world have to suck up to the garbage Communist Party?" one commentator called Yip Lou Jie said in an online forum, LIHKG, which is used by protestors in Hong Kong.