THEFT light - car shut down while driving

I was driving my wifes 99 Mountaineer, and after about 3 miles the CD player stoped working. Next the ABS light came on. I pulled over by the side of the road, and then the battery light came on...car computer on dash stopped showing. I turned around to head home, and then all the warning lights came on, and the lights began to dim in the car. It sputtered along for a little bit and eventually stopped. At first the lights didnt come on at all, but then they started working ok. Radio came back on. Lights flash when key removed from car...in an abnormal way.

The car clicks, but does not turn over. The THEFT light is now illuminiated and flashes. Key fob still works, so I turned that on and off a few times trying to reset alarm. Got a back up key/fob - didnt work. Tried disconencting battery, cleaning terminals... still nothing. I still have more tests to do on the electic system, but think the THEFT system is not letting me start back up. Not sure if its aftermarket alarm, since it was purchased used, and there is a remote starter. I cant figure out why it would shut down after driving a few miles like that which is throwing me off. Any ideas?

thats a battery I believe....I think a bad battery triggers a theft shut down (there is a reset?)

I had all sorts of strange things happen when the batter was going.