The leak occurred in Bensalem at the intersection of Bristol Road and Bensalem Boulevard, township police said in a Facebook post just before noon.
Officials asked residents to avoid the area until further notice, closed down nearby roads, and evacuated some homes in the immediate area.
Authorities characterized the leak as "high pressure," but did not identify a cause.
By about 1 p.m., Bensalem fire officials said the leak had been secured by PECO. Roads were reopened and evacuated residents were cleared to return home.
No injuries were reported.
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