PALM BAY, FLA. - Investigators searched Tuesday for one or more arsonists behind a string of stubborn wildfires that have destroyed at least 40 homes on Florida's Atlantic coast.

Firefighters in Brevard County were trying for the third day to contain fires that have scorched an estimated 10,000 acres, or more than 15 square miles, in and around the neighboring towns of Palm Bay and Malabar.

Though the high winds fueling the flames Monday had slowed significantly, officials worried about them spreading quickly in the dry conditions.

"We desperately need rain," said Palm Bay Fire Marshal Mike Couture. "We don't have any, and we're not projected to get any anytime soon."

Authorities said they had "a majority" of the Palm Bay fires contained and were getting better control over the fires in Malabar, where firefighters slept in shifts on cots in the volunteer fire station.

Palm Bay police were working with the state fire marshal's office and Brevard County Fire Rescue to investigate who set several fires that spread into a larger blaze.

"Some are caused by embers that are flying, but the locations of the fires indicated that these were initiated separately, which makes us firmly believe that an individual or individuals was involved in setting those," Police Chief Bill Berger said.