It appears that the mainstream news channels are ignoring a potential hijacking this morning for some reason. Ethiopian Airlines flight 702 diverted to Geneva today and that as a result all long haul flights to that destination are being diverted. (702 serves Rome and Milan normally)

The pilots appeared to have squawked the code (7500) for ‘Hijack’ part way through their journey from Addis Ababa. The 767 is now on the ground at GVA it is reported.

This is FlightRadars page for the flight.

Geneva airports arrivals page is here, showing the diversions of long haul flights.

AirlineReporter.com has provided a timeline here.

Having so recently taken 4 flights with this airline, I shall be watching what is happening with interest.

UPDATE:
The United flight from Newark appears to have gone to Milan as the return segment is showing operating 70 minutes late with the inbound aircraft coming from Milan. The Dulles flight is showing on time, with the inbound coming from Zurich.

UPDATE 2
BBC reporting that one hijacker has been taken in to Custody and that all crew and passengers are safe.
Their report is here.