A 6th person has died after the house explosion outside Pittsburgh, officials say

An explosion in a residential suburb outside Pittsburgh on Saturday morning left six people dead – including a father and son – and injured several others.

The explosion and large fire in Plum, Pennsylvania, a suburb northeast of Pittsburgh, marked at least the third time in 15 years a home has exploded in the borough. It destroyed three houses and damaged at least a dozen more, authorities said.

First responders who rushed to Plum Saturday found people trapped under debris and took three people to a hospital. The remains of five victims – four adults and one child – were also found at the scene.

Another person died Wednesday morning at a local hospital, the Allegheny County Office of the Medical Examiner said.

The deceased have been identified as Plum Borough residents Casey Clontz, 38 and his 12-year-old son Keegan; Heather Oravitz, 51; Kevin Sebunia, 55; Michael Thomas, 57; and Paul Oravitz, 56, according to Allegheny County officials. CNN affiliate WTAE confirmed Casey Clontz is Keegan’s father.

The incident appeared to begin when one house exploded, engulfing two neighboring homes in flames as well, according to the county. Multiple other homes were damaged with windows blown out.

Crews from 18 fire departments converged on the scene to put out the flames and sift through the rubble.

Fire officials are still investigating the cause of the explosion. Investigators are aware the homeowners of the exploded house were having issues with the water tank in their basement and are looking into that as a potential cause, “along with any and all other possibilities,” Allegheny County said in an update Monday.

“I heard this ‘boom.’ It was so loud that it woke me up. I thought it was thunder from the storms last night,” neighbor Alexis Typanski told CNN affiliate WTAE. “My water bottle fell on me instantaneously. I was shaking. It scared me so bad.”

By 4:30 p.m Saturday, the area was still considered an “active scene” and first responders were expected to remain there for hours, according to the county.

Gas was turned off in the area while emergency crews worked at the scene, authorities said at a news conference, adding multiple representatives from different gas companies were at the scene.

The Red Cross and Salvation Army are assisting residents impacted by the explosion, the county said.

Father and 12-year-old son killed in blast

A family statement provided to WTAE described Casey Clontz as “someone who always made people laugh.”

The statement adds Casey’s “biggest love” was his family.

Keegan is described as “100% his momma’s boy” in the statement. He loved spending time with friends, playing football and was described in the statement as “the perfect teammate.”

“He always supported his teams and just loved being a part of the game and everyone’s lives who were involved.”

The statement adds that Keegan “loved his sister, especially when he was able to give her a hard time as only a brother can.”

“Keegan and Casey were their most happy when they were spending time at the lake with their lake family & friends,” reads the statement. “They swam, did boating and loved cruising around in their golf cart. Keegan and Casey will be missed by so many and will continue to be loved by so many including their family, friends and community.”

Officials have not yet released the names of the victims. Amie Downs, the Communications Director for Allegheny County, told CNN that identifying the victims may involve dental records and DNA.

Pennsylvania Gov. Josh Shapiro offered his condolences for the victims and their families in a post on X, formally known as Twitter, on Sunday. “Lori and I are praying for family, friends, and neighbors who lost someone in Plum yesterday, and we’re grateful for the first responders who ran towards danger to save lives,” he wrote.

“The five Pennsylvanians who passed and their families are in our thoughts today,” the governor went on. “May their memories be a blessing.”

Authorities are investigating the explosion

Saturday’s explosion marks at least the third time in 15 years that a home has exploded in the borough. Another house explosion was reported in Plum in April of last year, according to Amie Downs, the communications director for Allegheny County. The cause of that explosion is still under investigation, Downs told CNN.

And in March 2008, a man was killed and a 4-year-old girl was injured in a home explosion in the borough, according to an NTSB pipeline accident brief. Two other homes were destroyed in that explosion and 11 were damaged, according to the brief.

The “probable cause” of the explosion was excavation damage to a natural gas distribution pipeline from a sewer line replacement in 2003 “that stripped the pipe’s protective coating and made the pipe susceptible to corrosion and failure,” the NTSB determined in its report published eight months after the incident.

Gas systems were “operating as designed” at the time of the explosion on Saturday, said Michael Huwar, the president of the gas service Peoples Natural Gas. Still, gas service was shut off to a number of homes in the neighborhood as a precaution.

A company spokesperson told CNN on Sunday its crews continue to work and coordinate with the Allegheny County Fire Marshal, which is leading the investigation.

Ring doorbell video obtained by CNN affiliate WTAE appears to show one of the homes exploding in a ball of fire, shooting up a thick plume of smoke and scattering debris in the area.

The aftermath of the blast and blaze can be seen in aerial footage of the neighborhood, which shows three structures completely burned to the ground, surrounded by heavy debris covering surrounding lawns and homes. Several cars near the scorched area could also be seen charred black and smoking.

CNN’s Celina Tebor, Artemis Moshtaghian and Zenebou Sylla, Sabrina Souza, and Zoe Sottile contributed to this report.

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