A woman opened fire inside celebrity pastor Joel Osteen’s megachurch in Texas on Sunday, sending worshippers rushing to find safety while two off-duty officers confronted and killed the attacker.
Two other people were shot and injured, including a five-year-old boy who was in critical condition.
The violence erupted shortly before the Houston church’s 2pm Spanish service was set to begin, just as the rest of the country was preparing for the Super Bowl.
The woman entered the enormous Lakewood Church – a building with a 16,000-person capacity that was previously an arena for the NBA’s Houston Rockets – with the boy who was later hurt in the shootout with police.
A man in his 50s was also wounded.
Details of the confrontation remain unclear and police have not released the woman’s identity or a possible motive.
The relationship between the woman and the boy, and who actually shot him and the man, is also unknown.
Houston police chief Troy Finner told reporters: “I will tell you this. That female, that suspect, put that baby in danger. I’m going to put that blame on her.”
The boy was in a critical condition at a children’s hospital, while the man was stable at a different hospital with a hip wound.
The shooting happened between services at the church that is regularly attended by 45,000 people each week, making it the third-largest megachurch in the US, according to the Hartford Institute for Religion Research.
Witnesses told reporters that they heard multiple gunshots.
Christina Rodriguez, who was inside the church, told Houston television station KTRK that she “started screaming, ‘There’s a shooter, there’s a shooter’.”
She and others ran to the backside of a library inside the building, then stood in a stairway before they were told it was safe to leave.
Despite the chaos, Mr Finner said the tragedy “could have been a lot worse” if the two officers had not “engaged” the woman when she opened fire.
They had been working as security at the church on Sunday and Mr Finner praised them for their quick actions.
The officers work for the Houston Police Department and the Texas Alcoholic Beverage Commission, respectively. Both have been placed on protocol-mandated administrative duty.
After she was shot, the woman told police she had a bomb, but authorities said no explosives were found when her vehicle and backpack were searched.
Mr Osteen said his congregation is “devastated”.
He added that he would pray for the victims and the woman and their families. It was not clear where he was at the time of the shooting.
“We’re going to stay strong and we’re going to continue to, to move forward,” he said.
“There are forces of evil, but the forces that are for us – the forces of God – are stronger than that. So we’re going to keep going strong and just, you know, doing what God’s called us to do: lift people up and give hope to the world.”
Texas Governor Greg Abbott said in a statement: “Our hearts are with those impacted by today’s tragic shooting and the entire Lakewood Church community in Houston. Places of worship are sacred.”
The church has grown tremendously over the past 25 years since Mr Osteen took over after the death of his father John in 1999.
Joel Osteen introduced an upbeat style of Christian televangelism that has captured a following of millions, with his televised sermons reaching about 100 countries. John Osteen founded the church in a converted feed store in 1959.