Over a dozen Afghan security personnel have been killed in suspected Taliban attacks.

The Defense Ministry said a suicide truck bomber struck an army convoy in the central province of Maidan Wardak on July 20, killing at least eight Afghan soldiers.

The ministry said another nine soldiers were wounded in the attack in Sayed Abad district.

No group immediately claimed responsibility for the assault, although similar attacks in the past have been blamed on the Taliban and Islamic State (IS) extremist group.

Hours earlier, an Afghan official said at least eight government security personnel were killed in a Taliban attack in the country's north.

Esmatullah Moradi, the spokesman for the governor of Kunduz Province, said Taliban militants stormed two security checkpoints in the early hours of July 20.

Moradi said five police officers and three government soldiers were killed in the hours-long clashes.

The Taliban has not commented on the attacks.

The attacks came as the Taliban intensify operations across the country, particularly in the country's north, where Afghan forces are more exposed.

Last week, Taliban fighters stormed the offices of country's main intelligence agency in the northern province of Samangan, killing 11 security personnel and wounding dozens of others, mostly civilians.

The Taliban continues to stage regular attacks across Afghanistan despite signing an initial peace deal with the United States in February.

That agreement was intended to pave the way for direct talks between the militants and the Afghan government over a permanent cease-fire and a future power-sharing deal.

Those talks were supposed to begin in March, but the process has stalled over the implementation of a major prisoner release.

The peace deal calls for Kabul to free 5,000 Taliban prisoners in exchange for the Taliban releasing 1,000 government captives.

So far, the government has freed more than 4,200 and the Taliban have let go around 800 prisoners.

With reporting by AP