By CBS3 Staff

CAPE MAY, N.J. (CBS) – An off-duty Philadelphia firefighter has died at a Cape May triathlon, fire officials confirm to CBS3. The firefighter was competing in the Escape the Cape Triathlon on Sunday morning.

It is unclear how the off-duty firefighter died at this time.

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The triathlon consists of a one-mile swim, a 23-mile bike ride and a five-mile run and swimmers began jumping off the Cape May-Lewes Ferry around 8:30 a.m. Sunday for the first leg.

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Another Philadelphia Firefighter also died Sunday morning from long-term medical issues.

The identities of the firefighters have not been released at this time.

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CBS3’s Dan Koob contributed to this report.