Continental Flight 3136 was on its way from Raleigh-Durham International Airport to Newark Liberty International Airport when it had to make an unscheduled landing in Washington at about 10 p.m.
Continental spokeswoman Julie King said the crew noticed an unfamiliar smell, so they decided to land at Dulles.
King says it's unclear what caused the smell, but passengers are continuing on to Newark aboard another aircraft just in case. She says the plane involved was an Embraer 145 and the flight was operated by ExpressJet, one of Continental's regional partners.
Earlier on Friday, a United Airlines flight from Shanghai, China, was evacuated on an O'Hare International Airport runway minutes after a pilot reported smoke in the cabin shortly before the plane's scheduled arrival, a United spokeswoman said.
One passenger on United Flight 836 was treated at a hospital, United spokeswoman Megan McCarthy said, but she did not know which hospital or the passenger's condition.
The plane's 258 passengers and 15 crew members were evacuated and bused to a terminal, according to Gregg Cunningham, a spokesman for Chicago's Department of Aviation.
One of the Boeing 777's four pilots reported smoke in the cabin around 3:45 p.m. CST. The plane landed minutes later and was evacuated as a precaution, McCarthy said.
Officials did not know the cause of the smoke.
In Columbus, Ohio, meanwhile, a bird flew into an engine of a Delta Air Lines flight during takeoff Friday night, forcing the pilot to make an emergency landing, an airline spokeswoman said. There were no reports of injuries to the 140 passengers and six crew members.
The jet took off from Port Columbus International Airport about 5:15 p.m. for Atlanta, Delta spokeswoman Ashley Black said. The crew initially thought the problem was a blown tire, Black said. A maintenance team later determined that a bird had flown into an engine.
The plane circled the Columbus area for about 90 minutes to burn fuel before landing.