Violence erupted in Afghanistan on Wednesday
when assaults killed five coalition troops and a suicide bomber killed two people.
NATO's International Security Assistance Force said the service members died in attacks in volatile regions of the country.
Four service members died in the east, three in an improvised explosive device, or IED attack and one in what was described as an insurgent attack. A service member died in an IED attack in the south.
A sixth ISAF service member died after a non-battle-related injury in eastern Afghanistan.
The precise locations and nationalities of the troops were not available.
In central Kabul, at least two people were killed and 32 wounded when a suicide bomber attacked a bus carrying government employees, authorities said.
The attacker drove a motorcycle toward a bus carrying staffers with the National Directorate of Security - the Afghan intelligence agency - and detonated explosives, said Mohammed Zahir, the head of the criminal investigation unit of the interior ministry.
A Taliban spokesman, Zabiullah Mujahid, said the militant group was behind the attack.
Among those killed, one was an intelligence agency employee and the other was a civilian, the agency said.
The wounded included six intelligence agency staffers, said agency spokesman Litusullah Mashal.
CNN's Joe Sterling contributed to this report.