Strange explosions in the sky

A few year ago, I was chilling on my balcony, looking up at the night sky. It was summer and I live in England. Suddenly, I saw an explosion, it was like an ourburst, almost like when a coronal mass ejection happens, the explosion went one way, covering half a circle going outwards. It lasted about 1-2 seconds. Obviously it’s hard to measure how far up in the sky it was but looked very high up, the whole thing covering maybe half a centimeter of the entire sky, at most. Around 5 min later it happened again, this time in another part of the sky, perhaps 1.5 meters from the where the original explosion took place. This time, my partner saw it too. I have seen quite a few meterors in my life and this looked nothing like it. What are your best guesses as to what it could have been? Have any of you seen anything similar? Thanks all