any accessory seizes you can kiss your serp belt goodbye. not to mention other things if you keep driving.

 

I have worked on 2 cars that would not run due in one case to a siezed compressor and the other case a siezed smog pump(4.6l mustang GT)

you said you were making a u turn- so the engine was probably running at idle- maybe making 20 or less HP- a seized compressor work be enough to stall the engine and probably n ot shred the serp. belt.
so like other gys -pull the belt and you will know in a matter of seconds if the engine itself is ok