At least 26 people were killed and 20 others were injured when a gunman stormed a church in rural Texas with a rifle this morning, Wilson County Sheriff Joe Tackitt and the Texas Department of Public Safety said.

Victims' ages range from 5 to 72, authorities said. Texas Gov. Greg Abbott called today's shooting in Sutherland Springs, about 40 miles southeast of San Antonio, the largest mass shooting in Texas history.

PHOTO: Investigators work at the scene of a mass shooting at the First Baptist Church in Sutherland Springs, Texas, Nov. 5, 2017. (Jay Janner/Statesman.com via AP) More

The alleged shooter, a 26-year-old man, is also dead after the massacre at First Baptist Church, bringing the total number of fatalities to 27, authorities said.

Here's what we know about the shooting:

Tragedy at church

PHOTO: Law enforcement officials gather near the First Baptist Church following a shooting on Nov. 5, 2017 in Sutherland Springs, Texas. (Erich Schlegel/Getty Images) More

The attack began at about 11:20 a.m., after a suspect was seen at a Valero gas station in Sutherland Springs, dressed in all black, the Department of Public Safety said. The suspect crossed the street to the church, got out of his vehicle and began firing at the church, authorities said.

The suspect then moved to the right side of the church and continued to fire, before entering the church and shooting more, authorities said.

As the suspect exited the church, a local resident grabbed his rifle and engaged the suspect, after which he dropped his assault-type rifle and fled, authorities said.

A citizen pursued the suspect, authorities said.

The suspect, who fled in a car, crashed and was later found dead in his vehicle in Guadalupe County, according to the sheriff and the Department of Public Safety. It's unclear whether he died from a self-inflicted gunshot wound or whether he was shot by another person, officials said at a news conference this afternoon at Stockdale City Hall, near the church.

PHOTO: Police vehicles gather at the scene of the SUV where the suspected shooter who opened fire at First Baptist Church of Sutherland Springs, Texas, drove off the road and was found dead on Nov. 5, 2017. (KSAT) More

Multiple weapons were found in the vehicle, authorities said, adding that the suspect had tactical-type gear and was wearing a ballistic vest.

The threat is believed to be over, Wilson County District Attorney Audrey Gossett said.

Authorities did not discuss a motive at this afternoon's news conference.

PHOTO: Authorities work the scene where the suspect of a deadly church shooting was found dead in his vehicle near the intersection of FM 539 and Sandy Elm Road in Guadalupe County, Texas, Nov. 5, 2017. (William Luther/The San Antonio Express-News via AP) More

14-year-old girl among the victims

Among those killed was a 14-year-old girl named Annabelle Renee Pomeroy, according to her father, Frank Pomeroy, who is a pastor at the church.

Annabelle “was one very beautiful, special child,” Pomeroy told ABC News by phone.

PHOTO: Annabelle Pomeroy, 14, was killed during a shooting at the First Baptist Church in Sutherland Springs, Texas, Sunday, Nov. 5, 2017. Her father, Frank Pmeroy is the pastor, but was not there at the time of the shooting. (Courtesy Sherri Pomeroy) More

Pomeroy said he was in Oklahoma this morning, a rare weekend that he wasn't at the church.

The other victims are all close friends of his, he said.

Last Sunday, Pomeroy delivered a sermon at the church, encouraging parishioners to "lean on the Lord," even when circumstances don't make sense.

"Trust in the Lord with all your heart and do not rely, or lean, on your own understanding," he said. "You see God's understanding is far greater and there may be things that are taking place that you don't understand but you still need to do what God's calling you to do."

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