DETROIT (WWJ) – Authorities say a natural gas leak is likely to blame for a fiery explosion at a commercial building on Detroit’s east side, which left three people hospitalized with injuries.

The situation unfolded just before 9 a.m. Tuesday at National Fleet Services at Grinnell and Grace avenues, off Gratiot Avenue just north of I-94.

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“It appears to have been a natural gas leak, compressed natural gas,” said Second Deputy Fire Commissioner Craig Dougherty. “The contractor there does conversions, converts gasoline vehicles to natural gas vehicles, and one of their tanks exploded, it appears.”

Reporting live from the scene, WWJ’s Mike Campbell said all four walls of the bottom portion of the building were completely blown out in the explosion, which also created a large fire.

Dougherty said only three people were inside the building at the time and all have been transported to local hospitals, although the severity of their injuries is unknown. One person was briefly trapped inside the building before being rescued. Another was reportedly thrown from the building due to the force of the explosion.

(credit: Mike Campbell/WWJ Newsradio 950)

(credit: Mike Campbell/WWJ Newsradio 950)

DTE Energy officials, police, fire, EMS and HAZMAT crews are on the scene. Officials are evaluating yellow bins around the building that apparently hold compressed natural gas. Power lines are also down and laying across puddles of water and snow, further complicating the situation.

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Officials on the scene say tensions remain high because another explosion could happen at any moment.

“Right now, we just want to keep everybody back just to be safe. Another explosion is possible, you never know, so it’s better to be prepared for the worst,” said one firefighter.

According to their website, National Fleet Services is an authorized compressed natural gas (CNG) modifier for the Ford Motor Company. The company converts vehicles to run on compressed natural gas and liquid propane gas.

(credit: Mike Campbell/WWJ Newsradio 950)

(credit: Mike Campbell/WWJ Newsradio 950)

A cause of the explosion remains under investigation.

Stay with WWJ Newsradio 950 and for the latest.

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