Investigators say there's no rhyme or reason to the fires and no one's been hurt.
"We're looking at somebody who is unsophisticated, poorly executed and poorly planned, but it's kind of dangerous and we want to make sure that we can catch them as soon as we can before somebody gets hurt," said Sgt. Jay Trisler of the Santa Monica Police Department.
Trisler told Eyewitness News reporter Leslie NMiller there were a dozen small fires on the other side of town last year, and the same people may be responsible.
Anyone with information on the fires was asked to call Detective William Heric at (310) 458-8410 or the 24-hour number at (310) 458-8495.
CNS contributed to this report.