PHILADELPHIA (CBS) — The Philadelphia Fire Department announced Friday that they could not determine the cause of the fire that killed four children in Southwest Philadelphia.

Four-year-old twins Maria and Marialla Bowah and brothers four-year-old Patrick Sanyeah and seven-week-old Taj Jacque died in the early morning hours on July 5, when the fire broke out at the rowhome.

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The blaze caused extensive damage to 13 homes and to five cars.  Five other residents were injured.

Fire officials say extensive damage to the initial area of fire destroyed the physical evidence required to determine the exact cause of this fire.

There is a wake tonight for the four victims of the fire.

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The funeral for the children will held Saturday.

Fire Commissioner Derrick J.V. Sawyer encourages residents who may have new information, to notify the Fire Marshal’s Office at 215-686-1362.

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