ALLENTOWN, Pa. (CBS/AP) — Five firefighters were injured during a large early-morning blaze at a historic restaurant in Allentown.

Dispatchers say the fire broke out about 4 a.m. Tuesday at Youell’s Oyster House in the 2200 block of West Walnut Street. The blaze was fully involved when firefighters arrived at the scene.

Two firefighters were injured during an exterior wall collapse and were taken to an area hospital for treatment. Two others were treated for minor burns, and another fell while assisting. All five firefighters are expected to be okay.

The restaurant has been in operation since 1905 and the Allentown location opened in 1992.

The fire was placed under control around 7:30 a.m. Officials say this is a total loss and demolition crews are on-scene.

The cause of the fire remains under investigation.

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