Afghan authorities on Wednesday arrested 35 soldiers who served on an army base in northern Afghanistan where Taliban fighters staged a deadly attack last week as fears grew they had inside help.
"So far 35 people have been detained and are being questioned in connection with the attack," said 209th Corps spokesman Abdul Qahar Aram, adding that they ranked from foot soldiers to colonel.
Over 170 soldiers were killed in the assault last week on the sprawling base, home to the 209th Army Corps, outside the city of Mazar-i-Sharif in northern Balkh province close to the borders of Turkmenistan, Uzbekistan and Tajikistan.
Gunmen in military trucks and wearing suicide vests stormed the base, killing unarmed young recruits as they ate lunch in the dining hall and prayed in the mosque.
Insider attack feared
The death toll has been unclear, with Afghan officials - who have been known to minimise casualties in previous attacks - ignoring earlier calls for exact figures.
So-called insider attacks - when Afghan soldiers and police turn their guns on their colleagues or on international troops - have been a major problem during the war which began in 2001.
Analyst Abdul Hamid Safoot said that the Taliban assault had highlighted multiple systematic flaws among Afghan forces, ranging from a lack of vetting to inadequate intelligence sharing.
"(The) Taliban know these weaknesses, they have people in the government," Safoot said adding, at least four of the attackers had served at the base.
After the insider attacks on the NATO trainers increased, the foreign mentors no longer allow Afghan soldiers to carry arms during training — Abdul Hamid Safoot
The assault has prompted widespread anger, with the defence minister and his army chief resigning Monday, leaving troops and police in disarray as the Taliban gear up for their spring offensive.
Afghan forces, already beset by killings and desertions, have been struggling to beat back insurgents since US-led NATO troops ended their combat mission in December 2014.
Their casualties soared by 35 percent in 2016, with 6,800 soldiers and police killed, according to US watchdog Special Inspector General for Afghanistan Reconstruction.