According to authorities, the entire church shooting in Sutherland, Texas, on Sunday was caught on video.

The video, which was allegedly caught on a camera positioned inside the First Baptist Church, shows the shooter entering the church and shooting at will.

As of Monday morning, investigators do not know why Devin Patrick Kelley, 26, carried out the mass shooting that left 26 people dead and 20 wounded.

Investigators said the victims ranged in age from 5 to 72 years old, with injuries ranging from minor to “very severe.”

Kelley lived in a suburb of San Antonio and didn’t appear to be linked to organized terrorist groups, a U.S. official told The Associated Press. The official said investigators were looking at social media posts Kelley may have made in the days before Sunday’s attack, including one that appeared to show a semiautomatic weapon (click here for photos).

Witnesses say the gunman was dressed in tactical gear when he opened fire on the church.

Kelley was confronted by an armed nearby resident who chased after him. He was later found dead, roughly five miles away. It’s unclear whether Kelley was killed by police or the armed resident, or by a self-inflicted gunshot wound.

Kelley previously served in the U.S. Air Force at the Holloman Air Force Base in New Mexico from 2010 until his discharge in 2014.

He was court-martialed in 2012 for assaulting his wife and his child. Kelley received a bad conduct discharge from the Air Force, in addition to confinement for 12 months and was reduced in rank.

Kelley worked as a security guard for a Texas water park this past summer, according to a resume under his name that appears online.

President Trump reacted to the shooting via a Tweet, as he travels overseas. “May God be w/ the people of Sutherland Springs, Texas. The FBI & law enforcement are on the scene. I am monitoring the situation from Japan.”