An investigation is under way after a natural gas transmission line ruptured in southern Marshall County.

Officials with Williams Energy said this was not an explosion, there was not a fire and no one was hurt. Even so, emergency officials were prepared for the worst.

The National Transportation Safety Board and other state agencies will be handling the investigation.

The 24-inch buried line ruptured around noon on U.S. Route 250, about 4 miles south of Cameron.

The line is off Reid Ridge near Fish Ridge and is owned by Williams Energy. Emergency Management Director Tom Hart said that the pipe rupture was so loud that people could hear it in the city of Cameron. The 911 center received about 25 calls about it.

A 3-mile radius was evacuated as a precaution until the gas was shut off, including residences on Reid and Fish Ridge.

Hart said that natural gas was being released into the air for about an hour until crews could get the gas valves shut off.

Those areas were all closed by state police as local fire departments, the Emergency Agency worked at the scene to determine what happened.

The Cameron Fire Department said the location of the line was about 300 yards down a hill and really not visible from any roadway.

The Cameron fire chief determined the scene was safe and residents were permitted to return also around 2 p.m., officials said. The road was also reopened at that time.

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