Airport officials said an airliner en route to San Francisco from Denver was diverted to Salt Lake City following a threat. But the threatening note did not contain a reference to a bomb as officials reported earlier.The jetliner resumed its flight after seven hours on the ground. United spokeswoman Robin Urbanski said she can't disclose the contents of the note. But she said the threat was considered credible. "I can't tell you what was in it, but I can tell you what wasn't," Urbanski told The Associated Press. The 757 carrying 168 passengers and six crew was en route from Denver to San Francisco when the note was found by a flight attendant in the galley. Earlier in the day, officials from the Salt Lake City International Airport and the FBI had cited reports of a bomb threat.FBI spokeswoman Debbie Dujanovic Bertram said in a statement Thursday night that she could not release details because of an "ongoing investigation." But she said law enforcement officials "searched the airplane for explosives and subsequently cleared the aircraft." Salt Lake City Superintendent of Airport Operations Dave Korzep said the Boeing 757 was sequestered away from the terminal. He said the FBI and airport police arrived at the scene to search the plane. Bomb-sniffing dogs also were deployed.The passengers and crew initially remained on board United Flight 741, and buses waited to transport passengers to the terminal when the all-clear was given.Airport spokeswoman Barbara Gann said a flight attendant found a note while the plane was in the air, headed to San Francisco, and turned it over to the pilot. "The note was threatening enough for the pilot to feel like he should divert," Gann said. A United representative said the flight was diverted as a precaution. It was diverted while over Utah, according to a radar track of the jet.The Transportation Security Administration issued a statement that said, "United Airlines Flight 741 from Denver International to San Francisco International was diverted to Salt Lake City International Airport due to a note found in the aircraft galley. The plane landed without incident at approximately 9:45 a.m. MST and taxied to a secure location. The plane was met by local law enforcement and TSA officials. All passengers have been deplaned and are being re-screened. The plane is being swept." The plane left Denver about 8:23 a.m. MST and landed at Salt Lake City International Airport about 9:45 a.m. The pilot announced the discovery of the "credible threat" to passengers over the intercom and said the plane would land in Salt Lake City within 12 minutes. "I was anxious, I'll tell you that," said Todd Rodvold, 44, of Denver, who was headed to California on business and called the experience a "movie-type deal." "I just wanted to get on the ground," he said. Mary Beth Winski, 65, of Durango, called the pilot's announcement "surreal." "You say a prayer right away," Winski's husband, Bob Winski said. "Then you start thinking, what are my options here? What are the options for the crew?" Bob Winski, 66, a pilot who flies search-and-rescue missions for the Civil Air Patrol, said the rapid landing indicated the pilot believed the threat was credible. "But nobody panicked," Mary Beth Winski said. Once on the ground, passengers sat on the plane for nearly an hour before handing over their IDs to FBI agents and being bused to the international terminal. Each passenger was interviewed by the FBI before being released. Urbanski said the plane was searched by Transportation Security Administration officials and cleared. Flight 751 was scheduled to take off from Salt Lake City about 5 p.m. Mountain Standard Time.