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The eastern shore of Virginia is mostly farmland, far quieter than the state’s better-recognized coastal areas like Virginia Beach or urban areas like Arlington. Sitting on the peninsula that separates Chesapeake Bay from the Atlantic Ocean, the area attracts hunters, fishermen and tourists in the warmer months, but other than farmland the area is pretty quiet.

So residents and law enforcement officials in Accomack County remain puzzled as to why at least 70 arsons have been committed in the area since November. The fires are almost always set at night, in abandoned or vacant buildings. But so far, who or what is behind them is anyone’s guess.

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So far, the fires have only damaged property, but some fear that might change if the arsonist is not caught soon. “No one has been hurt or injured to date, but the threat is very real,” says Corinne Geller, spokesperson for the Virginia Sheriff’s Department. “It just takes one for a resident or investigator to be injured.”

Accomack County, which spreads across 450 square miles of the peninsula, has 14 fire departments and one rescue crew — all volunteer — who get called out in the middle of the night to put out the flames, many of which are set in desolate areas. Accomack is one of the poorest counties in the state; of its 33,000 people, 18% of them live below the poverty level. Tomato, wheat, corn and chicken farms dot the landscape and the two largest employers are Perdue Products and Tyson Farms, which both have poultry processing plants in the county.

There are also as many as 800 abandoned or vacant properties, many over them overgrown. Most of the targeted structures are residential and all are abandoned or vacant. Geller says the fires are being set in a way that only allows them to be detected long after they are set. She said police also believe that with the timing of the fires — sometimes there will be more than one building ablaze simultaneously — that it is the work of a group of people rather than an individual. “The way they are set, the are able to get away with minimal detection,” she explained.

Although serial arson is alarming, it is not unique. Take, for example, the case of John Orr, a fire captain and arson investigator for the Glendale, Calif., Fire Department. As many as 2,000 suspicious fires from 1984 to 1991 went unsolved, including one that killed four people. It turned out that Orr himself had been the one setting the fires. He was convicted on three accounts of arson and sentenced to life imprisonment. (Orr still maintains his innocence.) Paul Keller, a devout bookkeeper from Everett, Wash., was fired from his job after setting fire to his desk; he subsequently went through a divorce, battled drugs and alcohol and eventually set what officials say were as many as 77 fires in four Washington counties between 1992 and 1993, including one at a retirement home that killed three residents. He was caught in 1993 and sentenced to 99 years in prison.

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There’s not necessarily any particular rationale for why a serial arsonist might set fires, says arson expert Kevin Kelm of Arson & Bombing Behavioral Analysis LLC. Reasons can range from thrill-seeking excitement to deep-seated psychological issues to a need for revenge. But there are three factors that can attract a serial arsonist to a target: availability, vulnerability and desirability. And the sparse farmland of eastern Virginia, with plenty of abandoned structures and few nearby witnesses, is a target-rich environment. “This is target selection,” says Kelm. “When you’re talking about abandoned structures, society doesn’t pay a lot of attention to it and there’s not a lot of security.

“This is an individual who is selecting crime sites,” he adds. “He’s looking for something that will burn.”

Officials in Accomack County have offered a $25,000 reward for information that leads to the capture of the suspect or suspects. There are some leads in the case and Geller says that more than 200 tips have been received from residents, but none that have concretely pointed to a particular person of interest or a motive. And with crime in Accomack generally low, there has not been an uptick in any other type of crime since the pattern began.

“Why is this guy doing this? I have no idea,” says Kelm. “But when we catch him and ask him, we’ll know.”