CONWAY, Mo. (AP) _ Bullets and bloody boot prints have convinced police that a man who killed his estranged wife and two other people in a Texas shooting spree this week also killed three people in south-central Missouri last week.

Howard Franklin Stewart, 36, who formerly lived in Missouri, committed suicide Tuesday on the front porch of his estranged wife's home in Corsicana, Texas, after killing her, her boyfriend and a former boss, police said.

In news conferences Thursday, police in Missouri and Texas said there was no question that Stewart also was responsible for the shooting deaths Sept. 16 of George Ray Brewer, 43, and his wife, Carol Brewer, 36, both of Niangua, and Steve Vestal, 38, of Conway.

Each was shot twice in the head. The motives for the killings remained unclear.

Authorities said the .22-caliber bullets that killed the Brewers and Vestal were fired from a pistol Stewart used in Tuesday's two-hour shooting spree in Corsicana, a town of about 25,000 people 70 miles south of Dallas.

Before shooting himself in the head, Stewart killed his estranged wife, Brenda Stewart, 34; his former boss, Dennis James Wade; and Edward L. Persons Jr., 30.

Stewart had lived in the Lebanon area about five years before moving to Texas in 1985. He apparently returned to Missouri this month, telling his family that he needed to get away and might hurt somebody, authorities said.

He arrived in Lebanon Sept. 10 or 11 and went to his parents' summer home. His parents arrived there a couple of days later and found their son building a carport.

On the morning of Sept. 16, Stewart left his parents' home in camouflage fatigues and carrying a back pack and a holstered pistol. Authorities say he told his parents that he was going to hitchhike back to Texas.

Sometime between 3 and 4 p.m. that day, George and Carol Brewer were shot in their van. Police believe they had picked up Stewart. Vestal was shot in the driver's seat of his pickup truck sometime after 6:30 p.m., and his body was left in the truck at a Lebanon park.

Laclede County Sheriff Lawrence Rifenberg said footprints in the blood in the Brewers' van and another on the left hip of Vestal's pants matched those made by heavy combat boots Stewart was wearing when he died.

Around midnight Sept. 16, Stewart returned to his parents' home. His backpack was missing, and his parents said he seemed tense and depressed. Stewart left Lebanon by bus Sept. 18 to return to Texas.