LOS ANGELES (CBSLA) — Crews were forced to pause their cleanup efforts in the Sepulveda Basin Monday after several propane tanks were found in a homeless encampment.

Cleanup crews targeted a 13-acre area along Bull Creek, next to Lake Balboa, for the third phase of a clearing effort in the Sepulveda Basin Wildlife Reserve.

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(credit: CBS)

The propane tanks, other refuse typical of homeless encampments and the overgrown, dry brush is exactly the mix of conditions that have contributed to at least two fires in recent months – and what city officials are trying to clear with this latest sweep of the Sepulveda Basin.

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Heavy machinery and trucks were brought in to assist with Monday’s cleanup operation. Some of the refuse found early on included shopping carts, old bicycles and precarious electrical setups consisting of extension cords connected to generators.

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Previous cleanup efforts have already removed 400 tons of debris and green waste from the Sepulveda Basin Wildlife Reserve. Officials say they will also enforce the sunrise to sunset hours of the park area to prevent new homeless encampments from popping up.