GALVESTON, Texas -- An arsonist who has been setting trees on fire in Galveston over the past four months has struck twice this week, KPRC Local 2 reported Friday.

The Galveston fire marshal said 34 trees have been set on fire in the past several months. The burnings began in March and intensified in May and June, officials said.

Cheryl Proctor lives across the street from the latest case.

"It's very unnerving to think someone's roaming around the neighborhood, right in your back yard," Proctor said.

The fire marshal said trees at an abandoned house in the 1600 block of Avenue M are the most recent targets in a string of tree burnings.

"That's very scary, especially in light of the dry weather we've been having. The houses are wood. They're very close together," Proctor said.

Officials said they believe more than one person is responsible. The majority of the incidents occurred between 1 a.m. and 6 a.m.

The arsonist has hit locations around homes and businesses throughout Galveston.

So far, no one has been hurt, but the fires have spread in some cases.

"One palm tree was next to a house. The house, of course, was an exposure fire and we had some vehicles damaged that were next to the palm tree," Galveston fire marshal Gilbert Robinson said.

Residents said it's hard enough to rebuild without without worrying about an arsonist.

"We're still recovering from the hurricane, so to have to go through this and for that to happen, it's just -- I'm still working on my house, so I didn't want to start all over again," Proctor said.

A $3,000 reward is being offered in the case.

Robinson said the trees will cost the city between $2,000 and $3,000 each to replace.