A Metropolitan Mosquito Control District helicopter spraying for mosquitoes in Anoka County was allegedly struck by a golf ball at The Refuge Golf Club in Oak Grove on Friday, officials said.

The Anoka County Sheriff’s Office is investigating the incident.

The golf ball allegedly struck and slightly damaged a helicopter under contract by MMCD, MMCD Board Chairman Fran Miron said. The pilot was able to safely return and land the helicopter, Miron said, and there have been no reports of injury.

The MMCD uses low-flying helicopters to apply a product containing a natural soil bacterium, or a mosquito-growth regulator, to wetlands and large areas of standing water, according to the MMCD. The treatment kills larval mosquitoes, preventing them from becoming adult mosquitoes.

“Safety is a top priority for us, and we are just really pleased that the helicopter was able to land safely,” said Miron, who also serves on the Washington County Board. “That treatment application is a very dangerous business because they fly so low, and they’re flying amongst trees.”

In 2016, a Bell 47 helicopter under contract by the MMCD exploded after it crashed into a detached garage in south Maplewood. The pilot, Michael Kramer of St. Charles, Minn., died at the scene.