VIDEO: What were they? Strange lights in the sky spotted over Northampton

A video posted by Dan Baker on his Twitter feed, @heebee123, show the flashing lights in the sky.

"They moved very slowly and quite low. The video isn’t great but it was the lights that drew our attention to them. The lights remained on and at the front they were white and red and at the rear they were blue. We counted at least 10," Dan told the Chron.

"Although someone has said how noisy they were - we thought they were really quiet for the height they were flying at....

"I’m not a mad conspiracy theorist, but not like anything I’ve seen before," he said.

Other social media users said they had also seen the lights.

Simon Khannet said: "Saw them over Kings Heath, I have never seen so many lights on an aircraft before. Didn’t show anything on the plane apps either. Moved slowly too and quite low. The lights were on and not flashing like normal planes. Counted 14 lights. Sound like a geek don’t I? But it was odd."

F-StopTom added: "I saw them too near Abington park. Made a jet sound as they went over but had loads of lights on. Not moving fast either."

Other users speculated they might be military planes as they did not show up on plane spotting apps.