Apple has taken down an app that uses crowdsourcing to flag sightings of U.S. immigration agents after coming under pressure from the Trump administration.

ICEBlock, a free iPhone-only app that lets users anonymously report and monitor activity by Immigration and Customs Enforcement (ICE) officers, was no longer available on Apple’s App Store as of Friday. The developer had confirmed its removal on Thursday evening.

“We just received a message from Apple’s App Review that #ICEBlock has been removed from the App Store due to “objectionable content’,” ICEBlock said in a social media post. “The only thing we can imagine is this is due to pressure from the Trump Admin. We have responded and we’ll fight this!”

The developer said last month that it had more than 1 million users. Even though it has been removed from the app marketplace, those who have already downloaded the app should still be able to use it.

The Associated Press reached out to ICEBlock for further comments on Friday.

Apple said it removed apps like ICEBlock due to the potential for risks that were raised by law enforcement.

“We created the App Store to be a safe and trusted place to discover apps,” the company said in a statement. “Based on information we’ve received from law enforcement about the safety risks associated with ICEBlock, we have removed it and similar apps from the App Store.”

U.S. Attorney General Pamela Bondi confirmed that her office had reached out to Apple on Thursday “demanding that they remove ICEBlock from their App Store.” In a statement sent to The Associated Press, she claimed that ICEBlock was “designed to put ICE agents at risk just for doing their jobs.”

Officials said last month that a gunman who opened fire on an ICE facility in Dallas had searched for apps that tracked the presence of ICE agents.

Bondi has previously said that crowdsourced apps that allow people to communicate about the location of law enforcement officers is not allowed — specifically referring to ICEBlock developer Joshua Aaron in a July interview on Fox News.

“We are looking at him and he better watch out because that’s not a protected speech,” Bondi said at the time.

But advocates say that tracking ICE activity is a form of free speech protected by the First amendment. They maintain that such platforms are primarily used among individuals looking to protect themselves from surprise raids or potential harassment from immigration officials.

Downloads of apps like ICEblock have surged as the Trump administration steps up immigration enforcement.

ICEBlock and other crowdsourcing apps like it are being targeted, but crowdsourced technology has become common in the app store, and is still available through other apps.

Navigation apps like Waze or Google Maps for Android phones have been in use for years. Part of their draw is that users are alerted to police speed traps by other drivers. Users of those apps have suggested they can be used to post updates about “icy conditions.”

Waze and Google Maps have not been targeted by U.S. officials.