Story highlights 5 U.S. service members are killed by a roadside bomb in southern Afghanistan

The Taliban claims responsibility for the roadside bombing

ISAF: 2 members were killed when an Afghan soldier turned his weapon on him

Another ISAF member is killed in an insurgent attack in northern Afghanistan

Eight service members were killed in three separate attacks in Afghanistan on Saturday, NATO officials said.

In one attack, a roadside bomb killed five U.S. service members in southern Afghanistan, U.S. and NATO officials said. The blast killed took place in the Maiwand district of Kandahar province, said the governor's spokesman, Javid Faisal.

The Taliban claimed responsibility for the attack.

Taliban spokesman Zabihullah Mujahid told CNN that 10 soldiers were killed in the blast, though the group is known for exaggerating the number of casualties.

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In a second attack Saturday, two members of NATO's International Security Assistance Force were killed when an Afghan soldier turned his weapon on them, according to an ISAF statement.

The incident in western Afghanistan is under investigation, ISAF said. The nationalities of those killed were not immediately released.

And in a third incident, one ISAF service member died after an insurgent attack in northern Afghanistan, ISAF said. No other details about the attack were released.