I would think to look carefully at all directions and, if visibility allows, pass the red light, then contest the fine with an "emergrncy vehicle passing through" defence. But what is the official position?
At least, that's how it works in Germany and Denmark. But I don't think Denmark has traffic light cameras. I've never seen them anyway. But I've seen them in Germany.
Of course, this is assuming you don't actually cross the entire junction, but rather just moves out into the junction, so the emergency vehicle can get through.
Although, if you are at a set of traffic lights and an emergency vehicle tries to get you to cross the line, what you should do is write down the registration plate and contact the relevant service to report the driver. The instructor on this course was ex-police, and according to him police, paramedics, and firefighters in the UK are taught to not do this under any circumstance, and if they are caught trying to persuade someone to cross a red traffic light then they can get in a lot of trouble.
The only case that trumps a red traffic light is when given a signal by an authorised person (e.g., police officers, traffic officers, etc).
I think under a literal interpretation of the law you are obliged to commit an offence if you are beckoned on across a stop line at a red traffic light; you can either refuse the instruction to be beckoned on (an offence) or you can cross the stop line (an offence). That said, there's plenty of habit of the beckoning taking precedent over the lights.
Basically the only time you see any police officer instructing traffic from a vehicle is when on a motorbike, typically when they're part of an escort.
Police cars will have dash cams, not sure on ambulances or fire engines.
That being said, scariest thing I did on the road was going through a red light to let an ambulance through at a motorway off-ramp. You better hope everyone else has heard those sirens.