By Syma Chowdhry

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PHILADELPHIA (CBS) — A fire ripped through four homes overnight in Port Ricmond, leaving five families homeless.

The blaze broke out around 1 a.m. Sunday at a row home along the 2800 block of Memphis Street and quickly spread to three other homes.

“Four actual fires,” said Battalion Chief Anthony Sneidar. “Some spread a little bit to the porch front on the fifth (home), but that was secondary to when we first arrived.

Less than hour later, firefighters had the blaze under control, but the hot weather made it difficult for them to do their jobs.

“For our folks, the heat,” Sneidar said, “making sure once they get their jobs done, getting them cooled down, getting them hydrated and making sure they are taken care of.”

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Cell phone video shows the fire spreading after a propane tank exploded.

“Four houses down over here, they had a barbecue grill and it was a nice explosion,” said Felix Demuro of Guardian Restoration. “They backed everybody up and that’s what really ignited the rest of the houses up.”

20 people, including five separate families, managed to escape safely and are now being assisted by the Red Cross.

“They seem to be in pretty good shape,” said Dave Schrader, spokesman for the Red Cross. “It’s a matter of getting them a place to stay and making sure they are taken care of mentally as well. We provide counseling because it can be very traumatic.”

In total, seven homes were affected by the blaze, four were destroyed.

The the cause of the fire remains under investigation.

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