Got back from work today, switched the kitchen lights on and the circuit breaker tripped. Assuming it was a bulb blowing, I reset the breaker and tried again. Same result. Then took out all six gu10 type bulbs so that there are no bulbs left on the circuit and tried again. Same result.
None of the bulbs are obviously blown. None of the sockets have obvious signs of problems. The other lights on the same circuit all work fine so long as I don't turn the kitchen light switch on.
I'm a bit stumped. What's the best way to go about diagnosing the problem?