Washington, April 8 : No threats were detected at the University of Oklahomas campus in Norman city after initial reports of an active shooter at the premises, officials said on Saturday. Oklahoma State Highway Patrol Trooper Eric Foster told CNN that the campus is safe and that no injuries were reported. Meanwhile, the University police has also issued an "all clear" alert. "After a thorough search, no threat was found. There is no threat to campus. Alert has been canceled," the university said in a tweet at 10.53 p.m. on Friday night. Just before 9.30 p.m., the university has announced on Twitter there was an active shooter and urged people to "take immediate action now. Run. Hide. Fight!" The warning was followed by another tweet indicating campus police were investigating "possible shots fired" on school grounds. "Avoid South Oval area. Shelter in place." /IANS