A United Airlines flight made an emergency landing in Denver this morning.United flight 867 was en route from Toronto to San Francisco when the pilot noticed some engine vibrations, said Rahsaan Johnson, a spokesman for the airline.

A United Airlines flight made an emergency landing in Denver this morning.United flight 867 was en route from Toronto to San Francisco when the pilot noticed some engine vibrations, said Rahsaan Johnson, a spokesman for the airline.

An Air Wisconsin regional jet was returned to Logan Airport this afternoon