[CLOSED - missing info] Bombers captured city with no capture units?

I recently played a game that I lost (I maybe could of won but it was taking too long, and we were almost definitely gonna lose as my ally was somehow not taking any land at all) What made me surrender wasn't the fact that I was going to inevitably be overrun. It was that my homeland provinces were magically taken by bombers when I had checked and made sure that they had no air transports, therefore no units to capture the city. There were no destroyers or anything like that. Yet they captured two capital cities of some nations. I thought bombers couldn't capture cities and could only soften up defenses/destroy units in minor cities.

Maybe they had stealth too, in addition to the bombers

Shouldn't it be revealed after they capture or get in range? Can helicopters or any other air unit capture cities? (they didn't use helicopters, but one of my other enemies who didn't capture it did previously use stealth air units)

Was it a map created by a player?
in the editor you can create units allow or disallow any unit to conquer, if this is the case you should contact the creator of the map

It was just the world map

Please follow the bug report format: https://atwar-game.com/forum/topic.php?topic_id=39713