DETROIT -

For the second time in about a month, Detroit’s police, fire and EMS workers had their radio communication system go out.

Just before 2 a.m. Tuesday, the system started going offline. Detroit Police Chief James Craig said the radio provider, Motorola, notified the department immediately and a backup system was put in place.

Craig said Motorola has been doing upgrades to the system for the past week without any issue -- but "corrupt data" is being blamed for Tuesday's problems.

But those who live and work in Detroit like Roger Mosley, concerns are growing that if you call for help, that call won't be answered.

"If I'm in trouble and someone else is in trouble then yah, they should have a better system then what they got," Mosley said.

Craig said dispatchers were able to get information out, but officers out on the street weren't able to respond back. Some first responders had to use personal cell phones and landlines to communicate.

911 call lines were not affected by the radio outage.

"Dispatch never lost complete communication, we're just not to an optimal state, what we’re used to," Craig said.

Local 4 cameras were rolling as a dispatcher announced the problem.

“Detroit Fire Department and emergency medical services, all units be advised the radios are coming in slowly. Continue to try to reach dispatch by radio. If you’re not successful, continue to communicate by phone,” she said.

When a complete outage struck the city in July, Craig had said it wouldn't happen again.

"I made a commitment that this would never happen again. Unfortunately, it did happen," Craig said.