MILWAUKEE -- Eyewitnesses tell FOX6 News they heard an explosion sound near 38th and Townsend Sunday evening, June 3rd -- where firefighters were on the scene checking on a report of the smell of natural gas.
FOX6 News is told two firefighters were seriously injured, and another three suffered minor injuries. All were transported to the hospital, along with one person living in the house, who was seriously injured.
FOX6 News is told one firefighter is in serious condition, one in fair condition, and three others were treated and released.
The civilian is reportedly in critical condition.
"I was at the hospital. All those people, I am their boss and they work for me and it is hard to take," Milwaukee Fire Department Battalion Chief Michael Romas said at the scene Sunday night.
FOX6 News had a crew on the scene Sunday evening, where it was reported that there was glass blown out of windows.
One eyewitness said he saw a man taken away on a stretcher and he looked to be badly burned.
There were multiple crews on the scene and several blocks were cordoned off.
Severl agencies were investigating Sunday night, June 3rd -- including the ATF, fire marshals, and gas and electric crews.
Right now, there is no determination as to what cause the incident.
Monitor FOX6 News and FOX6Now.com for updates on this developing story.