Officials say a tree fell on a wire, which sparked a fire, causing a gas leak.
YEADON, Pennsylvania (WPVI) -- Residents were evacuated in Delaware County on Saturday after a tree snapped, fell on a wire, and caused a natural gas leak.
The incident began just after 9 a.m. when officials were notified of a fallen tree along West Providence Road in Yeadon.
When crews arrived at the scene, they discovered a significant gas leak in the area.
"A large tree came down onto the power line. That arcing somehow did ignite a natural gas line in the street. There is a rupture in the gas line," said Timothy Boyce, Delaware County's director of emergency services.
Authorities say that roughly four hours later, the gas found an ignition source and a twin house sustained significant damage in an explosion.
"In the immediate area there were six homes, two of them exploded. There's an assisted living facility very close and an apartment complex. The fumes also got into those buildings, so that caused a larger-scale evacuation," said Boyce.
It took PECO officials several hours to contain the gas leak. During that time, more than 100 people were evacuated from the area, including people from the Grace Court Apartments.
Residents were taken to be sheltered at the nearby Evans Elementary School.
Approximately 50 residents of the apartment complex were able to return on Saturday night.
"I was inside the building when the alarm went off. I was also inside the building when they turned the lights off because I was busy watching my usual shows," said Jim Nelson from Yeadon.
Crews spent the rest of the day Saturday ensuring nearby homes were safe.
"Gas is underground. It can travel along the pipes that feed your home. So gas did move from the broken main in the street into several homes, that's why evacuations took place. But one of them eventually found a source and exploded," said Boyce.
"What caused the main to break will have to be investigated. Obviously, the tree caused an electrical event in the street and that caused the initial explosion," he added.
Yeadon and county officials along with the public utility commission say they will investigate and determine the next steps.