Classes and on-campus activities have been called off Friday at St. Louis Park High School after two separate fights involving students and adults on Thursday.

Two adults were arrested and some students and school staff members sustained minor injuries during the skirmishes that broke out at the end of the school day Thursday, a statement on the school district's website says.

The first fight was between two groups of students. Teachers and staff intervened. But the situation escalated when adults who do not work at the high school and knew of the earlier incident got involved in a fight with students, the school district said.

School staff and police officers who were already on campus broke it up, a city spokesperson said.

It was not immediately clear what led to the clashes, and district officials and police will investigate Friday and prepare for classes to resume next week.

"As of now, there is no confirmation about the involvement of weapons in either altercation," the district's statement said. "We are actively gathering information and working closely with law enforcement to understand the full scope of these incidents, including whether or not the incidents were racially motivated."

Along with classes, all athletic practices and a girls basketball game at home against rival Benilde-St. Margaret's have been canceled. The building will be closed to students, families and the public, the announcement said.

District officials said more information will be shared with families as they learn more about what happened. They also said additional layers of security will be in place when classes resume next week.

The St. Louis Park Police Department has not stationed a dedicated officer on the district's campuses since late August, when several agencies pulled their school resource officer programs in response to a tweak to the law governing how and when they're allowed to use force. The department instead assigned those agents, now called juvenile response officers, to patrol the neighborhoods surrounding district schools.

Those officers meet with school administrators every morning, district spokesperson Rachel Hicks said. One of them was at St. Louis Park High near dismissal time when the second fight broke out.

All other schools in the west metro school district were to be held Friday as usual, the statement said.