Nato employed attack helicopters to hit targets in Libya for the first time on Saturday, an alliance statement said.
"The targets struck included military vehicles, military equipment and fielded forces," the statement said, without giving details of the location of the strikes.
France and Britain said last month they were making attack helicopters available to Nato to step up pressure in an air war against Libyan leader Muammar Gaddafi's forces launched in March.
Britain's Sky News said the attacks were carried out by British Apache helicopters from HMS Ocean on the town of Brega in eastern Libya, site of important oil facilities.
Two targets were hit and an armoured vehicle at a checkpoint, a Sky correspondent on HMS Ocean reported.
The Nato statement said that the use of attack helicopters provided increased flexibility to track and attack pro-Gaddafi forces attempting to hide in populated areas.
Military analysts say it also greatly increases the risk of Western forces suffering their first casualties of the campaign, given the vulnerability of helicopters to ground fire.
The commander of Nato's Libya force, Lieutenant-General Charles Bouchard, said the first engagement had been successful and shown the unique capabilities of attack helicopters.
"We will continue to use these assets whenever and wherever needed," he said.
Military analysts say attack helicopters will allow more precise strikes against forces in built-up areas than high-flying jets used until now, while reducing the risk of civilian casualties.
Nato has said their deployment would not presage the deployment of ground forces in Libya, which Western countries have ruled out.