YOUNGSTOWN — The Mahoning County Courthouse and two buildings behind it were evacuated about 8:20 a.m. Wednesday after a crew working in an alley ruptured a natural gas line.

Purchasing Director Jim Fortunato said after the gas was shut off, the Youngstown Fire Department and Dominion Energy Ohio tested the air quality in the three buildings.

When the air tested OK, people were able to return at 9:30 a.m. The other two buildings are the county administration building on Boardman Street and Trinity United Methodist Church on Front Street.

Last week, Murphy Contracting started to dig in the alley to determine where drain and steam lines are located near an underground tunnel that runs from the county administration to the courthouse.

The contractor was working there again Wednesday when it ruptured the line, Fortunato said.

The crew was being cautious, “but it was just an unfortunate situation,” Fortunato said. He added, “You can call the utilities to mark everything, but it’s still hard to know sometimes where everything is.”

The crew eventually will make repairs in the tunnel, including replacement of steel beams that support some of the granite walls of the courthouse and a concrete slab over the tunnel.

The beams and concrete have been damaged by water that got under the decorative pavers in the alley.

Judge Anthony Donofrio’s courtroom and offices, which are on the second floor just above the area where the gas line ruptured, had some gas odor inside, the judge said.

On Aug. 12, Parella-Pannunzio of Austintown was working on a $6.9 million road-improvements project on Fifth Avenue close to the Western Reserve Transit Authority Fedearal Station, county jail and Youngstown Fire Department when the company ruptured a natural gas line.

Customers of WRTA had to leave the area while Dominion repaired that line.

erunyan@tribtoday.com