San Diego Fire-Rescue crews battled a stubborn fire Thursday in a riverbed along the city's boundary with Chula Vista.
No one was injured in the fire that was estimated to be burning an area as large as a football field near Fourth Avenue and Beyer Way.
The fire sparked at 1:00 a.m. in an area described as a marsh. Conditions were so muddy firefighters couldn’t access it, according to an SDFD spokesperson
Crews watched the fire to make sure it didn't spread and waited for the department's fire helicopter to arrive.
There are homes in the area but none were ever threatened. A cause is under investigation.