Cautious US aviation regulators announced Tuesday they have given oil company BP the first commercial license to fly a drone aircraft over land.

The Federal Aviation Administration gave BP and unmanned aircraft system (UAS) builder AeroVironment permission to use a drone for surveys of oil exploration and pipeline areas in Alaska's Prudhoe Bay area.

The surveys began on Sunday, using AeroVironment's hand-launched, camera-equipped, four and a half foot (1.4 meter) long Puma AE aircraft.

"These surveys on Alaska's North Slope are another important step toward broader commercial use of unmanned aircraft," said Secretary of Transportation Anthony Foxx.

"The technology is quickly changing, and the opportunities are growing."

The FAA has placed very tight restrictions on the use of drones as it studies how to regulate them and maintain public safety.

Earlier it permitted oil companies to use them for surveys over Artic waters. But with the cost of a UAS falling sharply, a number of companies, from mining companies to movie production and photography firms, are seeking licenses to operate drones on a commercial basis.

To get permission to fly, the companies must show their drones would not affect security and that they would be in the public interest.

A number of public agencies have already been authorized to fly drones for public service purposes, such as for security, rescue or weather forecasting.