Electrical Problems

[minisloth]

I've got a 1.6 2003 Civic that I'm having trouble with. The other day the battery warning light came on which I worked out to be what I thought was a problem with the alternator, as the battery had charge but wasn't charging any more while the car was used. The alternator was changed but the car cut out still. I got the battery checked out and was told that it needed a new one, which I bought and fitted. The car seemed to be working fine until this afternoon when it wouldn't start again. It didn't have enough power to turn over. After a jump start I started to drive home and it cut out. Again there wasn't enough power to start it. But this time when I turned the key all the warning lights on the dash came on and stayed on until I turned the wheel. This seemed to kill all the electrics totally.

I know I'm probably best just getting a garage to have a look at it but does anyone have any ideas as to what it could be?

Thanks

minisloth