Two children have been killed and 17 other people injured after a shooter opened fire on schoolchildren who were attending Mass at a Minneapolis Catholic school, authorities have said.
The assailant fired through the school's chapel windows at students sitting in pews and then died by suicide, officials said.
The children killed were eight years old and ten years old, they said.
"This was a deliberate act of violence against innocent children and other people worshiping. The sheer cruelty and cowardice of firing into a church full of children is absolutely incomprehensible," Minneapolis Police Chief Brian O'Hara told reporters.
FBI Director Kash Patel said the case was being investigated as an act of domestic terrorism and a hate crime targeting Catholics.
Mr Patel identified the attacker as Robin Westman, who public records show to be a 23-year-old resident of the area.
The shooting occurred two days after school started at Annunciation Catholic school, a private elementary school with about 395 students.
Watch: Minneapolis school shooting 'incomprehensible' - police chief
The school is connected to Annunciation Catholic Church, and both are located in a residential area in the southeast part of Minnesota's largest city.
Local TV showed parents ducking under yellow police crime tape and leading students out of the school.
At least two of the chapel doors had been barricaded from the outside using planks, Mr O'Hara said.
Officials said the shooter was armed with a rifle, a shotgun and a pistol and did not have an extensive criminal history.
Public records showed the shooter's mother had worked as an administrative assistant at Annunciation Church.
Officials also said they found a smoke bomb at the scene and were searching a vehicle in the parking lot.
Law enforcement was investigating multiple online videos to determine if they were posted by the shooter, according to two sources who spoke on condition of anonymity.
Local hospitals said they were treating 15 children and two adults, with many sustaining gunshot wounds.
There have been more than 140 shootings at US elementary and secondary schools this year, according to the K-12 School Shooting Database.
"Don't just say this is about thoughts and prayers right now. These kids were literally praying. It was the first week of school. They were in a church," Minneapolis Mayor Jacob Frey said at a news conference, visibly angry.
US President Donald Trump said he had been briefed on the shooting and said the FBI was on the scene. "Please join me in praying for everyone involved!" he said on social media.
The US Department of Homeland Security is in touch with local authorities and monitoring the situation, Homeland Security Secretary Kristi Noem said on social media.
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There have been three other shootings in the midwestern city since yesterday afternoon, including one at a Jesuit high school, that have together left three people dead and seven wounded, according to police.
Today's shooting did not appear to be related to the others, Mr O'Hara said.
The city recorded 54 homicides last year, down from 71 in 2021 but well above the 29 recorded in 2019.
In June, Minnesota also experienced an incident of political violence, when a gunman posing as a police officer allegedly assassinated a Democratic state politician and her husband in their home, and wounded another lawmaker and his wife.
The suspect was arrested after a massive two-day manhunt and faces state and federal murder charges.
Minnesota state law requires background checks for all gun sales and the state as a whole has a gun death rate below the national average, according to Everytown for Gun Safety, a gun violence prevention group.
Accreditation: Reuters/AP
