KABUL, Afghanistan (AP) — At least four Afghan soldiers have been killed in a roadside bomb attack on a bus in the capital.

Gen. Mohammad Zahir Azimi, spokesman for the Afghan Ministry of Defense, says the blast occurred Tuesday morning while army troops were on their way to the ministry in Kabul.

Azimi says six other soldiers and six civilians were wounded in the blast, adding that the bomb was detonated by remote control.

A Taliban spokesman tweeted that the group was claiming responsibility for the attack.

Taliban insurgents have stepped up their attacks against both Afghan and NATO security forces. Most international security forces are preparing to withdraw by the end of the year.

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