MILFORD — A gas leak in a Wildermere Beach neighborhood led to the evacuation of several houses Wednesday morning.

The leak, reported shortly after 8:30 a.m., was caused by a construction company crew that struck the line, a gas company spokesman confirmed.

The leak forced the evacuation of about 20 homes. Some went to neighbors’ houses, others were placed on a bus on Broadway.

Police closed roads between Brookdale Avenue and Grant Street.

Firefighters checked the gas levels in houses in the area every 20 minutes.

“We do have low levels of explosive gas in the area,” Milford Fire Battalion Chief Christopher Zak said. “We have some protective hose lines in place to protect the workers and firefighters.”

Police said shortly after 9:30 a.m. that Southern Connecticut Gas Co. has “identified the gas leak and are actively addressing the problem.”

Ed Crowder, a gas company spokesman, said once the leak is secured work will begin to repair the 4-inch main. The repair work was expected to last most of the day.

Crowder said about 30 customers were affected by the leak.

Two neighborhood residents — Frank Wilbur and Dennis O’Grady — said they noticed their water turned black. Battalion Chief Zak confirmed that due to the severity of the leak, firefighters had to use three fire hydrants while monitoring the leak, causing the discolored water.

Firefighters set up a command center at Broadway and Wood Avenue.

People were urged to avoid the area and use alternate routes.

Residents were allowed back into their homes around 11 a.m.