Residents using a community mobile app helped police confiscate more than 100 illegal fireworks this month, Concord city officials said.

Police set up a fireworks reporting tab on the city’s Concord Connect mobile app, and during the first week of July it drew 458 reports.

That is significantly more than the 320 fireworks calls made to the city’s 911 or non-emergency dispatch, showing that the reporting app worked as planned, Police Chief Mark Bustillos said.

“It allowed our 911 dispatchers to focus on responding to emergency calls, and it allowed our extra officers in the field to be dispatched immediately to fireworks-related calls, which resulted in the confiscation of more than 100 illegal fireworks.”

Through the app, residents could file real-time reports, alerting police to specific locations of people setting off fireworks. All fireworks are illegal in Contra Costa County.

The app collected data on where and when complaints were being filed, and residents could upload photos. Most reports came in between 9 p.m. and midnight and were more prevalent in certain parts of the city.

Police used the data to put four extra officers on patrol June 24-27 and July 2-4. A supervising officer monitored the real-time reports as they were logged and then communicated the locations to the team on patrol.

Average response times to the app-based reports were 5 to 15 minutes — faster than a fireworks-related non-emergency call being routed through 911 dispatch.

“This was a deterrence strategy that was intended to remind the community that fireworks are dangerous and illegal,” Bustillos said. “Our officers were visible throughout the community; they issued a handful of citations and took dozens of fireworks off the streets.”

The confiscated fireworks were logged, secured and then taken to the Contra Costa County Fire Protection District for disposal.