BANGOR, Maine — A stark rise in the number of copper wire thefts in recent weeks from Bangor Hydro-Electric Co. substations has the utility concerned for the safety of its employees and the potential thieves.

Company spokeswoman Susan Faloon said Bangor Hydro’s coverage area had not suffered many copper thefts until recently, but the problem is spreading.

“It’s hard to say whether people know the dangers or not,” Faloon said. “You can’t always tell just by looking at wires if they are charged.”

Bangor Hydro declined to publicize the location of the recent thefts because they don’t want to draw attention to areas where copper wiring is prevalent. Faloon did say the thefts occurred primarily in the northern parts of the company’s service area.

“Not only is it illegal to steal this copper wire, but the thieves could face injury or even death,” Bangor Hydro safety officer John Greaves said in a statement released Friday. “In addition, our employees could face injury from damaged equipment that they don’t know has been compromised.”

Faloon said no injuries have been reported in Maine from thieves touching live wires, but there was a death last year in nearby New Brunswick related to an attempted theft.

To address the growing problem, Bangor Hydro has increased surveillance and patrol inspections of its substations, including installation of motion detectors.

Copper thefts have increased in recent years as the value of the metal has risen. Bangor Hydro officials estimate the company has lost between $10,000 and $15,000 worth of wiring in recent years, and they worry the costs may have to be recovered by raising rates, according to the statement.

Copper grounding wires attached to some homes also have been a target for thieves. Bangor Hydro urged the public to report any suspicious activity to local authorities.