OAKLAND — Two adults and five juveniles were arrested and charged with burglary, criminal mischief and aggravated criminal mischief after police said acts of vandalism were committed at three schools that are part of Regional School Unit 18.

Oakland police who were called over the weekend found that Williams Elementary School and Messalonskee High School had both been broken into and several areas were vandalized, according to a news release by police. There also was damage to areas around Messalonskee Middle School and outbuildings between the schools.

The schools are adjacent to one another in Oakland, off Pleasant Street and Oak Street. The district serves Belgrade, China, Oakland, Rome and Sidney.

Charges were brought after investigators obtained video and physical evidence from the scene. The two adults who were charged, both 18, were Brandon Knight of Oakland and Zachary Knight of Oakland, who police said are cousins. The juveniles who were charged were not identified, but authorities said they’re from Oakland, Rome and Waterville.

Police said in the release that others may face charges as well and that the investigation continues.

The superintendent for the district, Carl Gartley, said Tuesday that several fire extinguishers were sprayed inside and outside the high school, and spray paint was used on the road and several light poles. Some of those involved were students in the district, but not all, he said. It was not clear how much it will cost to repair the damage.

Gartley said the incident is disappointing because the district has a commendable student body and faculty.

“The sad part is, the facility looks fantastic, the maintenance team has worked hard and the custodial team has worked hard,” he said. “We just had a few people who decided to do something stupid, and we have to deal with it.”