A United Airlines flight arriving in Chicago slid off its runway while landing at O'Hare International Airport Wednesday morning. At 7:45 a.m., just as snow began blanketing the city, United Airlines Flight 1977 from Seattle skidded beyond the turning point toward the gate, airline officials said. The snowfall by 8 a.m. was reported to have been reducing visibility on area roadways down below a mile near O'Hare and Midway, as well as in DuPage, Aurora and Morris. The Boeing 737 made a safe landing and at 9:30 a.m. and was being towed back to its intended gate with about 164 passengers on board, an airline spokesperson said. No injuries were reported. The plane was scheduled to land at the airport just before 5 a.m. Several passengers said crew members remained calm and handled the incident "smoothly." "I didn't know we were that close until the pilot made an announcement," said Ken Sajesk of Park Ridge. "No one was scared it seems like. Two kids were in first class and didn't make a sound." Crews at O'Hare were working to de-ice the runway grounds while authorities investigate the cause of the incident.