By CBSLA Staff

RIVERSIDE (CBSLA) — Four men – including three transients – have been arrested in a series of arson fires in Riverside in recent weeks.

No one was injured in any of the fires, three of which investigators determined were intentionally set by transients, Riverside Fire officials said.

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The most recent fire happened Sunday afternoon in the 6600 block of Van Buren, where firefighters found a semitrailer ablaze, not far from commercial buildings. Arson investigators determined the fire was set intentionally, and after circulating an image of a vehicle of interest, 36-year-old Christopher Ramos was arrested Tuesday.

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Firefighters responded to two fires on Aug. 16, one of which happened at about 8:40 a.m. near Main Street and the 60 Freeway. Vines on the south wall were found burning, and 35-year-old Paul Cowley was arrested by the California Highway Patrol.

Later that night, just before midnight, smoke was reported coming from a second-floor hotel room at the Hyatt Place hotel at 3500 Market St. Firefighters found a small fire was extinguished by the hotel’s fire suppression system, but not before it caused $100,000 in damage. Timothy Garner Dewan, 34, was arrested on suspicion of arson to an inhabited structure.

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This recent spate of arson fires kicked off on July 28, when firefighters found palm trees had been ignited in the 6400 block of Van Buren. The blaze was kept to approximately a half-acre, and no structures were damaged. Joshua Truslow, 26, was arrested on suspicion of arson of forest land.