Loud “bangs” that were likened to artillery fire were reported around Northampton, UK, on the night of April 22. Locals reported the noises via social media at around 10 PM local time.

According to the Northampton News, UK’s Ministry of Defence “completely ruled out the possibility of it being caused by one of their planes.”

Similarly, Northampton police officials, as well as Fire and Rescue Service, each stated they had received no calls about the sounds.

In June 2013, Northampton had previously been host to reports of mystery booms, which some speculated had emanated from below ground. Similar reports, though less widely publicized, occurred in May of the following year. The 2013 Northampton incident was also linked to power outages in the area, yielding similar descriptions of the sound appearing to resemble loud gunfire.

At present, the apparent cause of the sounds remains undetermined.