Nearby explosion

I walked past Holy Trinity Church this afternoon and saw it was closed due to ‘filming’. Two nearby streets were also cordoned off by police, and there was a severely dented police car in the middle of the road, which I’m assuming was related. I can see the church spire from my kitchen window, and while tidying up just now heard a loud bang. I looked up to see two more flashes/bangs and a definite explosion coming from the area of the church. There’s now rather a fair bit of smoke drifting over Old Town. It’s been five minutes and I haven’t heard any sirens, so presumably it was all planned!