Updated at 10:05 p.m. Nashville Police are warning residents to keep their doors locked and their eyes open for a partially nude man following a shooting early Sunday morning that left four people dead.There is reason to believe, police say, that the suspect at large is carrying at least one weapon that was not found during a search of the gunman's home."One of his guns, a pistol, remains unaccounted for," Metro Nashville Police tweeted Sunday evening.A man wearing only a green jacket shot three people dead at a Waffle House. One person later died at a hospital where two others are being treated for injuries. Police say the suspect fled on foot, and is still on the loose. Eye witnesses tell police he stripped his jacket off near the restaurant, went back to his nearby apartment and put on a pair of pants. He was last seen wearing only black pants.The police have identified the suspect as 29-year-old Travis Reinking of Morton, Ill. According to Metro Nashville Police spokesperson Don Aaron, Reinking drove his pickup truck to the restaurant in Antioch, Tenn., and shot people talking in the parking lot, then continued on and opened fire inside.When the shooting momentarily stopped, a Waffle House customer took advantage of the moment. James Shaw Jr. told reporters, "At that time I made up my mind ... that he was going to have to work to kill me. When the gun jammed or whatever happened, I hit him with the swivel door." Shaw then wrestled the gun away, and threw it behind the counter — prompting the gunman to leave."He is the hero here, and no doubt he saved many lives," Aaron said.The Tennessee Bureau of Investigation has added Reinking to its "Top 10 Most Wanted" list. Reinking was arrested by the U.S. Secret Service for being in a restricted area near the White House in July, 2017. He was subsequently released, Aaron said. Reinking's state firearm authorization was also revoked at the request of the FBI, and seized by Tazewell authorities in Illinois. Four of the guns seized were given to Reinking's father who, Aaron said, admitted to giving them back to his son. One of the previously confiscated firearms, the AR-15 was used in the shooting.Waffle House called it a sad day for the restaurant's family.Nashville's Mayor David Briley also took to Twitter to express his condolences.Adding in a follow-up tweet, "There's clearly more to be said about these circumstances, but for now I ask Nashville to pray for and rally around these victims." Copyright 2018 NPR. To see more, visit https://www.npr.org/.