South end of the building. South end of the building. >> Newly released footage captures the chaos as officers rush toward a burning Michigan church, confronting a heavily armed gunman. >> I got your back here, man. >> Body cam video shows the first officer arriving within moments, [music] sprinting toward the entrance as gunfire echoes through the air. >> Shoot him. Officers quickly confronted the suspect seconds before shots are exchanged and opened fire moments later. >> The suspect identified as 40-year-old Thomas Sanford, a Marine veteran who served in Iraq, was killed at the scene. >> But that doesn't mean that we didn't have >> inside the church. Panic erupted. People [music] ran for their lives as the sound of gunfire filled the air. Investigators say Sanford drove his truck into the Church of Jesus Christ of Latterday Saints in Graham Blank, Michigan before opening fire on Sunday morning. Police say he killed four people and wounded [music] eight others before setting the building on fire with gasoline. Explosives were later discovered [music] inside his truck and part of the church collapsed in the flames. According to authorities, the first officer reached the scene about 3 minutes after the initial 911 call. Within minutes, Sanford was dead. Shot by police who ran straight toward the sound of gunfire. Officials called it an act of targeted violence. Their quick response likely saved many more lives.