Police arrested a 33-year-old man Monday on suspicion of intentionally driving into pedestrians in Jefferson City, injuring a 61-year-old man and killing a pregnant woman and her 2-year-old son, according to investigators. >> Read more trending news Authorities said William David Phillips, of Jefferson City, swerved to intentionally hit Tillman Gunter, 61, while driving west on East Main Street on Monday afternoon. Police said Phillips traveled less than a mile before swerving again, striking Sierra Wilson Cahoon, 30, and her 2-year-old son, Nolan Cahoon. Cahoon, Nolan and Cahoon’s unborn child were pronounced dead at the scene of the crash, according to investigators. Gunter was taken to a hospital with injuries that did not appear to be life-threatening, police said. Authorities were called around 3:30 p.m. Monday after Phillips lodged the car he was driving into a building for Sustainable Aquatics, a fish hatchery, according to The Citizen Tribune and the Knoxville News Sentinel. Witness Bill Ray Jones told WBIR-TV he heard Phillips yelling that the “government told him to do it” as he tried to flee from the scene of the crash. 'He knew he had hit (Cahoon) and I'm sure he did because he was talking all crazy,' he told the news station. Sustainable Aquatics owner John Carberry told the News Sentinel he arrived at the scene of the crash within minutes Monday and found Cahoon and her son dead on the sidewalk. “There was a hole in the building and one of my employees ran out,” Carberry told the News Sentinel. “She had minor injuries. She ran up to the main building, and the perpetrator ran out of the hole and ran up and some local citizens grabbed him.” The crash ruptured several fish tanks and destroyed four fish systems, Carberry told The Citizen Tribune and the News Sentinel. He estimated about 2,000 wild-caught fish died after the crash caused more than 10,000 gallons of water to rush from the tanks. “I just want to let the police do their job and mourn the passing of this mother and child,” Carberry told The Citizen Tribune. “It’s very sad.” Phillips, of Jefferson City, was arrested on two counts of first-degree murder and one count of attempted first-degree murder. Authorities filed an additional murder charge against Phillips on Wednesday for the death of Cahoon's unborn child, WATE reported. In a news release, police said investigators believed 'this was an intentional act of violence toward randomly chosen pedestrians. “Investigators have determined that Phillips did not know the victims,” police said. In an arrest warrant obtained Wednesday by the News Sentinel, authorities said Phillips told investigators “a voice told him that he needed to go kill meth addicts.” After Phillips spotted Cahoon and her son, 'He said the voice told him that the baby stroller had meth in it so he intentionally drove into (the mother and child) ... killing them both,' the warrant said, according to the News Sentinel. Records from the Jefferson County Sheriff’s Department showed he remained jailed Wednesday. A spokesperson for Carson-Newman University, a Christian university in Jefferson City, told WBIR-TV that Cahoon and Nolan were the wife and son of Matt Cahoon, an assistant athletic trainer at the school. “Our hearts are breaking for one of our own,” Carson-Newman University interim President Paul Percy said Tuesday in a statement. “We take comfort in knowing that God also feels our pain and hears our prayers. Because of this, we ask for prayers for Matt and his family now and in the days ahead.” Officials at First Steps Preschool at the First United Methodist Church told WBIR-TV Nolan was a happy student who always gave out hugs and high-fives. 'He was a joy,' the preschool’s director, Jessica Lawson, told WBIR-TV. 'He would walk through the door smiling every morning.' Officials at Carson-Newman University started a fund to benefit the Cahoon family. Those wishing to contribute can donate online to The Randall and Kay O’Brien Benevolent Fund on the university’s website.