Mobile Mast?
Its quite likely there is a phone mast there.
We had this problem outside my Uncles house when attending his funeral.
The car would not lock or start (its a keyless ignition).
We had to wait about 30 minutes or so in the end and finally it started working (in the mean time I tried a new battery). It happened again when we returned this time for an hour or so. its never failed before or since.
I spotted other motorists having issues and on talking to neighbours it seems they have been having problems with their car alarms and immobolisers for a few months,. On and off their remote key fobs just don't work.
After a bit of a chat it seems a mobile cell was placed in the church tower at the end of the road, seems problems started around that time although they hadn't put it together.
My dads problems was worse as he has a keyless car. So can't even use the ruddy key. So when buying your next car remember if that thing don't work you are stuffed.
So I guess if there is a similar problem there - all thieves have to do is hang around and wait.