DIXON (CBS SF) – Two men were killed and two others were seriously burned after a recreational vehicle caught on fire in Dixon early Tuesday morning, according to the Dixon Fire Department.

The blaze was first reported at 4:25 a.m. on the grounds of the Dixon May Fair at 655 S. First St., Dixon Fire Chief Greg Lewis said.

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Firefighters arrived to find an older model, class A RV in flames.

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An investigator on the scene of a fatal RV fire at the Dixon May Fair grounds, March 19, 2019. (CBS)

An investigator on the scene of a fatal RV fire at the Dixon May Fair grounds, March 19, 2019. (CBS)

According to Lewis, the two found dead hadn’t been removed from the RV as of 5:45 a.m. The two injury victims – who were outside the RV – suffered second- to third-degree burns and were transported to a hospital.

Lewis said the burns the victims suffered indicate the blaze likely started near the front of the RV, but the official cause was under investigation. No other RVs or trailers were affected by the blaze.

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