Russian entry into Turkish airspace lasted 'seconds': U.S. official

WASHINGTON (Reuters) - The United States believes Russia's incursion into Turkish airspace on Tuesday likely lasted only a matter of seconds before Turkey shot down a Russian warplane, a U.S. official said, saying the assessment was based on preliminary indications. The official, who spoke on condition of anonymity, said the United States was still investigating the incident. (Reporting by Phil Stewart; Editing by Doina Chiacu)