Gunmen on a motorbike fired at the vehicles and then set them on fire after pouring petrol on them in the Dasht suburb of the provincial capital Quetta, local police official Ismail Sumalani told AFP.
There were no casualties in the attack, which happened when the trucks had stopped at a roadside tea stall, he said.
No group has claimed responsibility for the attack but the Taliban has in the past said they carried out similar attacks to disrupt supplies for more than 130,000 US-led international troops fighting in Afghanistan.
Taliban and Al-Qaeda-linked militants frequently launch attacks on NATO supply vehicles in the northwest and southwest regions of Pakistan, which border landlocked Afghanistan.
Most supplies and equipment required by foreign forces in Afghanistan are shipped through Pakistan, although US troops increasingly use alternative routes through Central Asia. (*)
Editor: Kunto Wibisono
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