LONDON -- The British Airline Pilots Association is warning of a looming catastrophe unless drones are subject to tougher regulations.

The association demanded the compulsory registration of drones Monday after Gatwick Airport briefly closed its runway over safety concerns when a drone was spotted in the area.

Authorities diverted four EasyJet flights. One British Airways flight was sent to Bournemouth Airport.

Get Breaking News Delivered to Your Inbox

The union's flight safety specialist, Steve Landells, says the incident shows "the threat of drones being flown near manned aircraft must be addressed before we see a disaster."

There have been several near-misses between drones and aircraft in Britain, with sheer chance averting collision in some cases.

Under British rules, a drone operator must be able to see it at all times and keep them away from planes, helicopters, airports and airfields.