Are Mousavi and Karroubi Under Arrest?

There are reports of their fleeing Tehran, now besieged by bussed-in pro-Khamenei fundamentalists, and reports of their being placed under arrest. The regime is clearly trying to have them killed:

Taghi Karroubi said guards assigned to his father, Mehdi Karroubi, stopped providing security for him Monday, apparently on police orders. The measure means that the elder Karroubi cannot go outside safely, his son said, describing the situation as "quasi house arrest."