(DALLAS) — At least one victim was killed and four others were injured when a gunman opened fire inside a crowded Texas church on Sunday morning before he was shot to death by an armed security guard, officials told ABC News.The shooting occurred at 10:57 a.m. at the West Freeway Church of Christ in the Fort Worth suburb of White Settlement and was captured on the church’s livestream of the service, officials said.The federal Bureau of Alcohol, Tobacco, Firearms and Explosives tweeted that they had a team “en route to a reported shooting at the West Freeway Church of Christ in White Settlement, Texas.”Three people were taken to hospitals, including one who remained in critical condition. Another victim died en route to the hospital, officials said.The shooter, whose name was not immediately released, was pronounced dead at the scene, according to a spokeswoman at MedStar Hospital in Fort Worth.Two other people suffered minor injuries when they hit their heads attempting to flee the church, officials said.”Our hearts go out to the victims and families of those killed in the evil act of violence that occurred at the West Freeway Church of Christ,” Texas Gov. Greg Abbott said in a statement. “Places of worship are meant to be sacred, and I am grateful for the church members who acted quickly to take down the shooter and help prevent further loss of life.”The church service was going on when the gunman appeared to stand up and confront an usher, according to the livestream video.The footage shows the gunman wearing a long coat taking a step back before pulling what appeared to be a shotgun from his coat and firing point-blank on the usher and another member of the congregation. A security guard standing near the front door of the church returned fire, hitting the suspect, according to the video.As chaos erupted, members of the congregation ducked under pews as others who appeared to be armed rushed toward the gunman, the video shows.”Everything is under control. Our security team did everything they needed to do,” a church leader is heard in the livestream telling terrified members of the congregation.The church leaders urged everyone to stay calm and file out of the sanctuary.”We had a gentleman that came in armed to do harm,” the church leader says in the footage.Church members can be heard screaming and crying in the livestream, including one person who yelled, “I love you.””Our hearts and prayers go out to all the families that were affected by this incident,” said Fort Worth police spokesman Mike Drivdahl at a news conference.Texas Attorney General Ken Paxton tweeted his office will assist in the investigation if needed.This is a developing story. Please check back for updates.Copyright © 2019, ABC Radio. All rights reserved.