HEARTBREAKING details have emerged about the Minneapolis mass shooting that killed two children and injured at least 17 people.

Families were observed in tears, embracing one another as they made their way out of Annunciation Church following a gunman opening fire through a window during a school Mass on Wednesday morning.

A gunman clad entirely in black discharged a rifle through the windows of the church while numerous attendees were present for the morning service at the school, which caters to preschool through eighth grade, located in southern Minneapolis.

Minneapolis Police Chief Brian O’Hara reported that the shooter, dressed in black, aimed at the students in a “deliberate act of violence” before ultimately turning the weapon on himself.

An eight-year-old and a ten-year-old child were killed while sitting in the church pews, O’Hara said.

Police said 17 other people were shot, 14 of whom are children. Seven children are in critical condition, the hospital said.

The hospital said that doctors are currently treating nine pediatric patients, with their ages ranging from six to 14.

As students evacuated the school, witnesses reported seeing victims in shock at the scene, according to the Minneapolis Star Tribune.

A little boy was heard saying to his dad, “I don’t feel safe,” as children filed out of the building in their school uniforms, the outlet said.

Another child was seen holding a stuffed animal as he left the crime scene.

“Children are dead,” Minneapolis Mayor Jacob Frey said at a press briefing on Wednesday.

“There are families that have a deceased child. You cannot put into words the gravity, the tragedy or the absolute pain of this situation.”

The Catholic school had its first day of classes on Monday.

Mass started at 8:15 am on Wednesday and the shooter opened fire through the window just 15 minutes later.

The unidentified shooter was in his early 20s and carrying a rifle, a shotgun, and a pistol, police said.

A parent who was attending the church service said students were packed into pews when the killer opened fire.

“He just pepper-sprayed through the stained-glass windows into the building, 50 to 100 shots,” the unnamed parent told the Star Tribune.

“This is terrible,” he said. ”This is evil. I don’t know how you defend against this.”