Gas has been siphoned out of parked cars, construction equipment and even school buses in recent weeks. Gas station employees across the state are on high alert as more and more patrons are driving off without paying first to avoid the astronomical prices.

It doesn’t stop there.

Heating fuel tanks, many at summer residences in eastern Maine, have been targeted for the liquid gold that lies inside. Some tanks have been punctured and drained, likely into portable plastic jugs a few gallons at a time. Last weekend at a seasonal camp in Washington County, an entire 100-gallon propane tank was taken.

It seems no type of fuel – and no amount – is safe these days, and public safety officials fear the recent trend is only the beginning.

“It’s no different than recent thefts of copper pipes or catalytic converters from cars, which have increased in value,” Washington County Sheriff Donnie Smith said this week. “This [fuel thefts] isn’t something we saw even a couple years ago, but if the value is there, people will take it.”

Lt. Christopher Coleman, head of the Maine State Police Troop J for Hancock and Washington counties, said troopers in his unit lately have been running from one fuel theft to the next.

“It’s tough to keep up and track these, but we do the best we can,” he said. “If gas or heating fuel goes above $5 a gallon like people think it’s going to, we’re only going to see more.”

While they couldn’t access specific numbers – a theft is listed as a theft, whether it’s shoplifting a pair of shoes or stealing a car – both Smith and Coleman said fuel thefts have increased considerably.

Because resources are thin and the patrol area so vast, however, Smith said officers have been unable to determine whether any of the rampant thefts are connected.

A couple months ago, nearly 600 gallons of heating fuel was taken from Cherryfield Foods, a Down East company that processes blueberries and other fruit. Thieves have preyed on construction equipment that remains parked overnight at job sites. The school buses that serve SAD 37 in western Washington County recently were outfitted with gas cap locks after someone siphoned gallons from the tanks. One bus even ran out of fuel during a morning run. None of those cases has been solved.

The phenomenon isn’t limited to Down East Maine either. Earlier this month in Portland, a man reportedly siphoned several gallons of jet fuel from a plane parked at the city’s airport. In Vermont this week, state police are urging truckers to lock their fuel caps to prevent thefts of diesel fuel. The call comes after 190 gallons of diesel fuel was stolen over the weekend from two tractor-trailers parked at an automotive business in St. Johnsbury.

Gas station drive-offs and siphoning are the most common methods of stealing gas, but reports of tank and line puncturing are starting to trickle in to police departments and repair shops across the country.

Some veteran mechanics and law enforcement officers say it’s an unwelcome return of a crime they first saw during the Middle East oil embargo of the early 1970s.

In Maine, Sheriff Smith said fuel thefts are particularly difficult to investigate because little evidence is left behind.

“People are either using the fuel themselves and it’s gone, or they are selling it cheap,” he said. “Obviously, we need help from the community on this, so if people are seeing suspicious activity, they should notify local police.”

Coleman said that residents and businesses can take steps to mitigate thefts. The sale of locking fuel caps has become increasingly popular, for instance.

“If your house is better equipped or protected than your neighbor’s, chances are the thieves are going to go next door,” he said. “I certainly wouldn’t leave a full gas can behind my shed.”

The Associated Press contributed to this story.