NATO says nine of its soldiers have been killed in Afghanistan, including four in a helicopter crash in the south.

Three Australian soldiers and an American service member were killed Monday, when their helicopter went down in Kandahar province.  A NATO statement says there are no indications of enemy involvement in the crash.  Seven other Australian soldiers were wounded.

NATO says separate bomb explosions killed two other service members, including an American, in the south. A small-arms attack killed another service member in the region.  And NATO says two of its soldiers were killed in a roadside bombing in eastern Afghanistan.

A recent United Nations report noted an increase in violence in Afghanistan, with the number of roadside bombings jumping 94 percent in the first quarter of this year compared to 2009.

Also Monday, Britain announced its 300th fatality in the nine-year Afghan war after one of its soldiers died from wounds suffered in a June 12 explosion in southern Helmand province.

British Prime Minister David Cameron said Monday that Britain was "paying a high price" in Afghanistan and that British forces would leave the country as soon as Afghans can "take security for their own country."

Britain has about 10,000 troops in Afghanistan, the second largest foreign contingent after the United States.

NATO Secretary General Anders Fogh Rasmussen expressed his condolences to Britain in a statement and said international forces have helped to ensure that Afghanistan is no longer a safe haven for terrorists.

Separately, Afghan officials say at least 14 suspected Taliban prisoners were released Monday as part of efforts to persuade insurgents to make peace.

The prisoners included 12 detained by the U.S. military at Bagram Air Base and two suspected suicide-bombers in Afghan custody.

The decision to review their cases came after last month's peace assembly or "jirga" called by Afghan President Hamid Karzai made recommendations on how to get militants to lay down their weapons.

Some information for this report was provided by AFP.