As first reported by Business Insider:

Apple has removed ICEBlock, an app that allowed users to monitor and report the location of immigration enforcement officers, from the App Store.

“We created the App Store to be a safe and trusted place to discover apps,” Apple said in a statement to Business Insider. “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.”

Obviously the reasoning is a load of crap, but if Apple wants to operate in a given country they have to follow local laws and respond to government requests. This is far from being an unique situation.