In each case they ruled out gun crime.

At the same time, the number of other crimes involving guns, such as armed robberies, has also plummeted to just six since December.

Chief Supt Chris McKeogh said he was pleased with the results so far.

He said: “The project was launched to cut gun crime and protect communities from harm in areas which had historically experienced higher levels of gun crime.

“While it remains too early into the project to say whether we have achieved this, I am greatly encouraged by the progress made so far.

“Since the technology was switched on in December, we have recorded a number of loud bangs and responded as though they were genuine firearms incidents.

“By speaking to local people, reviewing nearby CCTV and searching the area on foot and with specially trained dogs, our officers have quickly been able to discredit these.

“We expected this to happen and the system learns to filter-out such noises.”