Lynnfield, MA – Natural gas safety has become a hot-button issue in the state, but residents in one Massachusetts neighborhood say they’ve smelled gas wafting through their homes for 12 years.

“All my neighbors smell it,” said Conyers. We’re just reading the paper and watching the news and expecting the worst.”

Conyers reported the gas leak to National Grid, but the only response from a crew that came out to inspect the location was to place a red flag in the ground. Conyers said that a National Grid worker told her that the smell in the neighborhood was not strong enough to warrant immediate action.

“They came and a week after I met this gentleman, a flag showed up and they still haven’t done anything. I don’t know what the flag means. They still haven’t contacted me since,” said Conyers.

Three home explosions have rocked the state in the last three months, including incidents in Scituate, Gloucester and Somerset. Two of the blasts proved fatal. A fourth explosion occurred in Manchester, N.H., on Tuesday, although investigators have not determined the cause of the blast.

State regulators announced Thursday that they will launch an investigation into the safety of the aging natural gas infrastructure in the state.

“We always encourage our customers to call us when they smell gas or detect a problem,” said National Grid spokesman Nick Stavropoulos at a news conference. Stavropoulos said that National Grid’s system is in the best shape that it’s ever been.