INDIANAPOLIS â The family of seven had much to celebrate recently. Youngest sons David and Alberto Covarrubias had just made First Communion, and their mother, Emma Valdez, had marked a birthday. Her adult daughter had just found a new home. The seven, described as well-liked and good neighbors, were found dead in their house late Thursday in what city officials described as the worst mass murder in Indianapolis in 25 years. The crime rocked their working-class neighborhood about a mile east of downtown. "Right now we're kind of in shock," said the Rev. Carlton Beever, pastor of St. Philip Neri Parish, where the family attended Mass each Sunday. Police on Friday arrested one suspected triggerman, but continued their search for the main suspect â 28-year-old ex-convict Desmond Turner â and possibly two other men a witness reported seeing running from the house. A search of a home for Turner just blocks from the shooting scene turned up empty Friday night after police officers fired tear gas in and broke down a door. Deputy Police Chief Tim Foley said James Stewart, 30, was arrested without incident after a traffic stop Friday afternoon and would be charged with murder. Foley said both Stewart and Turner were believed to have fired shots at the victims. Officers found the three children â Alberto Covarrubias, 11; David Covarrubias, 8; and Luis Albarran, 5 â dead on a bed and the bodies of the four adults scattered inside the home. Police identified them as Valdez, who turned 46 in April; her husband, Alberto Covarrubias, 56; her daughter and Luis' mother, Flora Albarran, 22; and her son, Magno Albarran, 29. Frank Dodson, who lives across the street from the family, said he thought he saw Flora Albarran being pulled into the house just before the shootings. Police said she had just finished running errands for her new home when she returned to her mother's house to pick up Luis. The attackers were armed with assault rifles, police said. "We have reason to believe that ... especially Mr. Turner, made statements prior to the robbery that these people were pretty much presumed dead before they ever went in the house," Foley said. Turner returned to the neighborhood in November after serving 3 1/2 years in prison for drug possession, criminal recklessness and firearms violations, authorities said. Foley said investigators believed the shooters knew at least one of the victims and that nearly 30 shell casings from an assault rifle were found at the home. By Friday afternoon, mourners had left flowers and an angel statue along a sidewalk out front. At St. Philip Neri, a parish of mostly working-class whites and Hispanics, a regularly scheduled Mass was celebrated for the family Friday morning. The family had been involved in the parish for at least 10 years, Beever said. "All seven were active," the priest said. "Everyone kind of knew them and liked them." The Covarrubias boys attended religious education classes at St. Philip, and the whole family came together to see them celebrate their First Communion a few weeks ago. "It was a special event," Beever said.