Iran's Artesh: A Karrar UAV intercepted 3 US aircraft - a P-8, RQ-4, and MQ-9.
https://dnws.ir/415433 

Artesh says that the aircraft had entered Iran's ADIZ while Zolfaqar 99 exercise was ongoing, and did not heed Iranian air defence's warnings. They changed course and left Iranian ADIZ once the Karrar was airborne.

Context: due to congested airspace above Persian Gulf, and ageing fighter aircraft, Iran rarely uses its air force for patrol and interception. Most unwelcome aircraft are radioed by air defence crews and told to leave or get shot down by ground-based air defences (SAMs).

Using Karrar is a somewhat less confrontational and oddly more "classic" way of dealing with the problem. Iran displayed Karrar UAV with IR seeker and warhead being used as an air-to-air suicide drone last month. https://twitter.com/maysam21901/status/1294283083802390528?s=20

The idea itself isn't without merit. Air policing in peacetime doesn't need to involve super-expensive manned fighters. A relatively simple UCAV can still provide such a role if equipped properly, while reducing maintenance load on main manned combat aircraft.

However, Karrar's design is essentially that of a target drone's, and its lack of sophistication degrades ability to be used in the sensitive role of air policing.

A proper platform would be able to carry IR guided missiles, and provide all-round visibility (via sensors and cameras) for a ground controller to be able to act/react more like a real pilot (maybe with some kind of VR helmet arrangement). Supersonic capability would be a big +

If this idea is carried forward in such a way, we might see ancient B-52s intercepted by robots in future. P-8s/RC-135s too. Maybe even UCAV-on-UAV interceptions.