The Columbus Division of Police believes two armed robberies on East 12th and 13th avenues in the last week are tied to a Jan. 14 double murder on West Norwich Avenue.”We think that these are connected due to similar methods of entry,” Homicide Detective Dana Farbacher said. The incidents are geographically close, and in all three, the armed suspect entered residences through unlocked doors, he said.”We wanted to get the information out,” Farbacher said. “Then we can investigate further into the connection.”Police are searching for a tall, thin male, black, armed with a handgun, Farbacher said. As of 11:45 p.m. Monday, the police had no suspects, nor had they made any arrests.Early Sunday morning, five Ohio State students were robbed and one of them was shot when a man matching police’s description walked into their unlocked apartment on East 13th Avenue carrying a gun.The assailant allegedly shot OSU student Josh Sixt, a resident of 156 E. 13th Ave., in the knee. He was transported to University Hospitals where he had surgery Sunday. He was discharged Monday afternoon. Adam Hoskinson, a sophomore majoring in political science, believes his roommate was shot because he twitched while asleep in a chair.”He was sleeping and may have flinched,” he said. “There was really no reason to shoot him.”The residents of the townhouse left their door unlocked because they were waiting for other roommates to return.Jeremy Kuhnash, a senior majoring in computer science, said he heard the door open and then saw a gun pointing in.The gunman then sent him to a bedroom after snatching money from his wallet.”When I heard shots, I Supermanned it out the window headfirst,” Kuhnash said.Drew Boyer, a sophomore majoring in business, said it is not overkill to keep all the doors locked.”All it takes is once for the door to be open,” he said.Sunday’s robbery was the second in the campus area in the last week. On Jan. 19, an armed man walked into an unlocked apartment at 171 E. 12th Ave. Brooke, one of the residents, said she got back from the neighbors and did not lock her door because she was waiting for a pizza.”My boyfriend Patrick and I were expecting a pizza,” said the OSU student, who spoke on condition of not giving her last name. “We heard the door handle jiggle expecting it to be him, and in walked a gunman.”She said the gunman said “sit down and shut up, this is not a joke,” and told them to tear the phone cords from the wall. He then asked if anyone else was in the apartment and walked Brooke and her boyfriend up the stairs at gunpoint to a roommate who was washing her face.Brooke said the gunman demanded at least $30 or he would shoot somebody. They did not have any money, so they gave him a watch and a portable CD player.When they thought he was gone, they returned downstairs, locked the door and called 911.On Jan. 14, Patrick Pryor and his girlfriend Loretta Long were slain in a shooting in an apartment on West Norwich Avenue after a gunman entered through an unlocked door.President William “Brit” Kirwan, said Monday many faculty and staff members are troubled by the incidents.”We need to do more, giving this highest priority,” he said, adding he is pleased with the efforts of the police.University Police Chief Ronald Michalec said he wanted to assure everyone the situation is under control. He said University Police are assisting city police to enhance safety in the campus area.”The police have been trying to inform staff and students to protect themselves,” Michalec said. “We want to prepare students in advance by driving home the fundamentals of personal protection and individual safety.”He said last week University Police canvassed the area east of High Street with brochures outlining safety tips.