Nine people were killed during a shooting at a service at a historic African American church in Charleston, S.C., on Wednesday, one of the deadliest gun attacks at a house of worship in the United States. Here are five key points to know about violence at houses of worship in the United States:

  • This incident ties for the largest mass murder at a house of worship in the U.S.
  • There is an uptick in violence at houses of worship. In 2014, there were 176 deaths at a religious institution.
  • There have been 13 mass murders at a house of worship since the Birmingham, Ala., bombing in 1963.
  • About 60 percent of violence at religious institutions include guns.
  • The last mass killing at a house of worship was at a Sikh temple outside Milwaukee in 2012.

The Charleston shooting ties for the most people killed during a mass murder at a faith-based institution in recent memory, according to Carl Chinn, who runs what is considered to be the most extensive database on violence at houses of worship by searching Google for news. The FBI defines mass murder as four or more killed in a single act, typically at one location.

“It’s certainly one of, if not the most, vicious attacks I’ve seen at a faith-based organization,” said Chinn, who described the shooting as the 13th mass murder at a faith-based organization in the country.

[Dylann Roof, suspect in Charleston church shooting, has been captured]

Nine people were killed in 1991 at the Wat Promkunaram temple near Phoenix, the worst mass murder in Arizona history. Johnathan Doody, tried three times for the execution-style murders of nine people at the Buddhist temple, was sentenced in 2014 to 249 years in prison.

Some are comparing the Charleston shooting to the bombing at a church in Birmingham in 1963. Four members of the Ku Klux Klan planted dynamite at the 16th Street Baptist Church, killing four girls and 22 others. Chinn describes that bombing as the first mass murder at a faith-based organization in U.S. history.

[Clementa Pinckney, Charleston preacher and state senator, remembered for calls for justice]

By Chinn’s count, fatal attacks at houses of worship have grown from a handful a decade ago to 74 last year. But he notes that it’s become easier to catalog incidents online in recent years, which could partly account for the perceived increase.

In a targeted attack in 1974, the 70-year-old mother of the Rev. Martin Luther King Jr., was fatally shot as she played the organ at Ebenezer Baptist Church in Atlanta, six years after her son was assassinated.

Guns have accounted for about 60 percent of the violence that has taken place at houses of worship, Chinn said. In a press conference Thursday, President Obama condemned gun violence more broadly.

“The fact that this took place in a black church obviously also raises questions about a dark part of our history,” the president said. “This is not the first time that black churches have been attacked, and we know the hatred across races and faiths poses a particular threat to our democracy and our ideals.”

Since 1999, Chinn has been searching the Web for news of church violence. As a building engineer at Focus on the Family, Chinn was a first responder to a 1996 hostage crisis at the organization. In December 2007, Chinn was in the hallway of New Life Church in Colorado Springs, Colo., when the congregation was attacked by a gunman. Two people were fatally shot before the gunman committed suicide.

[For Charleston’s Emanuel A.M.E. church, shooting is another painful chapter in long history]

In 1980, a gunman entered First Baptist Church in Daingerfield, Tex., and yelled, “This is war!” He opened fire, shooting 15 people, killing five.

“It’s still rare that you’re going to encounter a homicide like this,” Chinn said. “But I believe there’s an uptick in violence at faith-based organizations.”

Before Wednesday’s shooting, the most recent mass murder at a house of worship occurred Aug. 5, 2012, at a Sikh temple south of Milwaukee. Six people were fatally shot. The gunman, who was shot in the stomach by a police officer, committed suicide by shooting himself in the head.

The Charleston shooting “is different,” Chinn said. “This wasn’t suicide. It seemed very calculated.”

According to Chinn’s research, more than half of attacks at religious institutions are prompted by domestic violence spillover, personal conflict or robbery.

The graph has been updated. 

[LIVE UPDATES: The latest from the streets of Charleston]

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