The PECO Energy Company has received hundreds of calls Saturday from residents in Bucks, Chester, Delaware and Montgomery counties about a gas odor in the area.
More than 900 separate calls were placed to PECO between late morning and 9:30 p.m., according to officials for the energy company.
Workers with the utility company and firefighters responded to the area, but neither crew has detected gas -- indicating there are no leaks, according to authorities.
There may be a problem with their "system odorizers," which is a piece of equipment that puts a smell into the naturally odorless gas, according to information PECO provided Montgomery County officials.
It is unclear why residents are detecting the scent across such a large region, PECO officials said.
The investigation is continuing and authorities urge PECO customers to call 1-800-841-4141 if they smell gas.