PHILADELPHIA (CBS/AP) — Crews resumed their search Wednesday for a 13-year-old boy who went missing while swimming with friends in a rain-swollen creek two days earlier.

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Brandon Boyle was swimming with his 11-year-old brother and their friends in the Pennypack Creek on Monday when he was swept away by the roiling waters. His brother was found clinging to a ledge and was rescued.

Police continued searching the area for Brandon on Tuesday and Wednesday but saw no signs of him. Brandon’s great-aunt, Judy Williams, said authorities are calling the search a recovery effort, not a rescue effort, but the family isn’t ready to call it that.

The younger brother was taken to the hospital for observation, but officials say he’s OK.

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Police said all available emergency services forces, including divers, police officers and firefighters, were working on the search effort. The efforts of rescue divers are limited by the tide and weather, but officers have been supplementing by patrolling the area on foot.

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