Alva Review-Courier -

The ability of drones to interfere with airliners — and inconvenience their passengers — has now been demonstrated on two continents, and the problem is likely to get worse as the number of small, unmanned devices multiply.

Law enforcement authorities are trying to figure out who flew a drone so high and so close to Newark Liberty International Airport that incoming flights were held up briefly during a peak hour at one of the nation's busiest airports.

Flights resumed within about 30 minutes — much more quickly than after a similar incident last month at London's Gatwick Airport.

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