One of the suspected shooters at the deadly New Year’s Eve shooting in Mobile, Alabama, used an illegal device to turn a pistol into a machine gun, police said.

Mobile Police Chief Paul Prine said at least one of the shooters had used an illegal switch device to modify a normally semi-automatic Glock pistol into a fully automatic one.

Fully automatic weapons require a high level of government licensure to legally obtain. Use of such a switch makes the weapon illegal and more dangerous, experts say, because the small pistol could effectively dump more than a dozen rounds in as little as a second or two.

The shooting, which police said was sparked by neighborhood gang activity, left one person dead and nine others injured.

Police identified the dead victim as Jatarious Reives, 24, and said one of the suspected shooters was shot in the chest and is in the hospital. Police said the suspect, who has not been identified, will be charged as soon as the medical treatment is finished.