That should sound familiar. It's yet another public request for Apple to hack into one of its phones. Recall the FBI asked Apple to help it unlock the iPhone used by San Bernardino shooter Syed Farook back in February (Apple refused).
In this case, it's the iPhone 4s of an off-duty Turkish police officer who gunned down the Russian ambassador to Turkey, Andrei Karlov, in an art gallery in Ankara December 19. Turkish police believe the contents of the iPhone 4s could contain evidence of the shooter's association with international terrorist groups.
Russia is sending a technical team to Turkey to try hacking into the phone. Apple has so far not said if it will participate, but (especially now that the request has been made public) the company almost certainly will not.