Prime Minister of Australia Julia Gillard speaks to the media regarding the Australian soldiers killed in Afganistan, during the Pacific Islands Forum in the Cook Islands on Aug. 29, 2012. (Marty Melville/AFP/Getty Images)

Five Australian troops were killed in two separate incidents in Afghanistan on Wednesday and Thursday, making it the bloodiest 24-hour period for Canberra in the war and adding to growing concern about attacks on foreign troops by rogue Afghan soldiers.

Three troops were relaxing at their base in southern Uruzgan province when they were shot at close range by an Afghan man wearing a military uniform, the vice chief of Australia’s Air Defense Force told reporters in Sydney.

The shooter managed to escape by scaling a fence after the incident late Wednesday, Air Marshal Mark Binskin was quoted as saying. Two Australian soldiers were wounded.

Binskin said two other Australian troops died Thursday when their helicopter rolled over in Helmand province, a militant stronghold also in the south. The NATO-led coalition said there was no enemy activity in the vicinity at the time of the crash; the incident is under investigation.

Australian Prime Minister Julia Gillard called the loss of the five military personnel the single worst day for her country in a war since the Vietnam conflict.

The deaths from Wednesday’s shooting attack, also known as an “insider” or “green on blue” attack, bring the total number of foreign troops killed by rogue Afghan security forces in August to 14. Except for the Australians killed Wednesday, almost all of the victims were Americans.

As concern and suspicion build between foreign forces and Afghan troops, NATO has ordered soldiers to carry loaded weapons at all times. NATO said this week that a quarter of the recent insider attacks were conducted by Taliban-led insurgents who had infiltrated the ranks of Afghan forces.

The Afghan government, while blaming the attacks on “spies” from neighboring countries, has also adopted some measures to stop the trend. Afghan President Hamid Karzai condemned the latest attack in a statement from Tehran, where he is attending a summit of the Non-Aligned Movement. Karzai attributed the recent attacks to groups seeking to create mistrust between the foreign troops and the Afghan forces they are training and equipping.

Attacks on Afghans are also continuing. On Wednesday evening, the chief of the provincial council of Ghazni province was gunned down by militants, a spokesman for the Taliban and a provincial official reported.