Fuel pump or anti-theft?

Hi ... I just bought a 91 Miata with 76K miles on it from the auto auction. I test drove the car prior to the sale, it ran perfectly.

When it came through the auction block, the car was being pushed. I thought it ran outta gas or something. After I bought it, I tried to start it. The engine would turn over for a split second, then sputter and die.

I remember hearing this same sound when I bought a Chevy S10 with anti-theft issues, so I inspected the fuse box under the hood. Someone disconnected a red wire related to the anti-theft system. As soon as I connected the wire, the alarm went off. I turned it off with the wireless remote. To make a short story long, the engine still wouldn't crank over. There's a black box underneath the dash (passanger side) with anti-theft system related wiring (it says Pursuit Alarm System on the box). One of the clips (with a red and green wire leading into the black box) are detached. There's also a thin black wire that's detached. I don't know if these necessarily have to be connected to anything. The guy bidding against me probably tampered with the car. I just don't know if it's anti-theft related, fuel pump related, or both. Any ideas? Thanks in advance ...