WARREN (WWJ/AP) – Officials say two people were hurt and 80 other employees were evacuated following an explosion at the GM Tech Center in Warren.

GM said this incident was unrelated to the Chevy Volt or any other production vehicle, but instead was a result of “extreme testing” on a prototype battery.

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Deputy Fire Chief Gary Wilkinson said the explosion happened around 8:45 a.m. Wednesday in the research facility’s Alternative Energy Center. He said the cause of the explosion most likely was related to a lithium battery.

Wilkinson said two people were injured during the explosion. One was treated at the scene and the other was taken to an area hospital. A statement issued by GM said five additional workers were being evaluated by medical personnel. All injuries appeared to be non-life threatening.

Firefighters saw smoke and extinguished a small fire that was confined to the Alternative Energy Center laboratory. GM spokesman Mike Meyerand  said the only part of the Tech Center that was evacuated was the area where the battery lab is located. He said the rest of the massive complex continued operating as normal.

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WWJ Auto Beat Reporter Jeff Gilbert said lithium-ion batteries do have a tendency to overheat.

“At these laboratories they stress the batteries to the maximum to make sure they’re safe for drivers. So, this is an area where they do a lot of their very important research and it just goes to show that sometimes things happen,” said Gilbert.

Wilkinson said the Tech Center covers about four square miles, from Van Dyke to Mound Road and from 12 Mile to 13 Mile.

The explosion remains under investigation.

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