A shooter opened fire Wednesday morning during Mass at a Minneapolis Catholic school, killing two children and injuring 17 other people before killing himself, officials said.

Minneapolis Police Chief Brian O’Hara said the shooter — armed with a rifle, shotgun and pistol — approached the side of the church and shot through the windows toward the children sitting in the pews during Mass at the Annunciation Catholic School.

The school was evacuated, and students’ families were later directed to a “reunification zone” at the school. President Donald Trump and Minnesota Gov. Tim Walz said in separate social media posts that they had been briefed on the shooting.

AP video by Mark Vancleave