Students returned to Jose Ortega Elementary School today after police determined a bomb-threat note found on campus this morning had no merit, San Francisco Unified School District officials said. School officials called police about 8 a.m. to report the note, and responding officers evacuated the school, which is located at 400 Sargent St. near San Francisco State University's main campus, said SFUSD spokeswoman Gentle Blythe. Students and school personnel waited outside while police investigated the campus. Just before 11 a.m., the school district sent a message via Twitter that the buildings were found to be safe. “Students at Ortega ES are returning to school, and @SFPD has given the all clear,” the tweet read.