TUCKER, Ga. --
Firefighters blamed a buildup of methane gas for a series of explosions that blew at least three manhole covers into the air Sunday night along Lawrenceville Highway in Tucker.
Southbound lanes of Lawrenceville Highway near Jimmy Carter Boulevard were still closed on Monday morning. All lanes of the busy highway were closed for about 10 hours.
Firefighters used fans to clear the methane gas from manholes and sewers in the area.
Investigators are trying to determine what sparked the explosion.
"It could have been a power surge," said Capt. Tommy Rutledge, of the Gwinnett County Fire Department. "It could have been any number of things, but right now we're not sure what exactly caused the explosion."
Workers from AT&T were called out because the explosions damaged some of their underground equipment in the area.
"There are about 8-10 vaults in this area," said Rutledge. "We found high concentrations of methane gas."
There's no word on when the southbound lanes of Lawrenceville Highway will reopen.
Commuters who usually drive south of Lawrenceville Highway should use Stone Mountain Freeway/Highway 78, according to Channel 2 Action News traffic reporter Mark Arum.
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