(Reuters) - A gas well exploded near Charleston, West Virginia, on Tuesday, setting four houses on fire, an emergency spokesman said. It was not immediately known if there were any injuries.

The explosion was reported at 12:41 p.m. ET, said Michael Slater of the Metro Emergency Operations Center in Charleston.

The explosion in Sissonville, about 10 miles north of Charleston, set four houses on fire, and they were still burning at mid-afternoon, Slater said.

Nearby Interstate 77 was closed to traffic in both directions, as was Route 21.

"Flames are shooting very high in the area," he said.

A nearby nursing home was not damaged by the blast, he said.

A spokeswoman said West Virginia State Police were preparing to release further details about the blast imminently.

(Reporting and writing by Ellen Wulfhorst; Editing by Cynthia Johnston and Philip Barbara)