US warplanes have killed up to 20 suspected rebels in an air strike in Afghanistan, the US military says.
The strike came after a patrol came under attack from rebels in the south-west province of Helmand and called for air support.
A US military spokesman said there were no casualties in the patrol, which was made up of both US and Afghan forces.
There has been renewed violence by suspected militants in the area in recent months.
Suspected Taleban rebels had pinned down the convoy with rocket and small-arms fire in Grishk district on Sunday, the US military said.
US aircraft and attack helicopters were then called in.
"Initial battle-damage assessments indicate 15 to 20 enemies died and an enemy vehicle was destroyed," a US statement said.
US military spokesman, Lt Col Jerry O'Hara, said: "When these criminals engage coalition forces, they do so at considerable risk.
"We will close with and destroy those that stand against Afghan and coalition forces at every opportunity."
The US has about 18,000 troops in Afghanistan tackling remnants of the Taleban that was ousted in late 2001.
Violence has increased, particularly in the south and east, following a lull over winter, raising fears for security in September's planned parliamentary elections.
Nearly 400 people have been killed in Taleban-linked violence this year, most of them suspected militants but also around 30 US troops.
Helmand province was also the scene of a fatal shooting on Saturday in which a judge, intelligence officer and education worker were killed by unidentified gunmen.
The three were returning from a dinner party to the capital of Helmand province, Lashkar Gah.
Provincial security chief Amanullah blamed the attack on the Taleban.