The attack involved at least five Taliban, one of whom blew himself up at the entrance to the site in the city of Gardez to clear the way for the others.
The attack set off fierce clashes, and Afghan officials say the siege was still underway.
On May 20, two civilians, two police and five militants were killed after Taliban stormed a local bank in the city, 100 km south of Kabul.
The last attacker held out for hours inside a dining hall as security forces worked to evacuate kitchen staff sheltering nearby, Tabasim said.
An Afghan soldier opened fire on foreign troops at a military base in northern Afghanistan, leaving at least seven USA troops injured.
LSU names Scalise honorary CWS coach, will send game ball
It was the 22nd straight victory for No. 1 national seed OSU (55-4), which will continue CWS play at 4:05 p.m. The double-elimination tournament features two brackets, and Sunday's games were the first in the second one.
Paktia police chief Toryalai Abdani put the toll at six police killed and 12 wounded.
Afghan security forces inspect the aftermath of a suicide bomb blast in Gardez, Paktia Province, Afghanistan June 18, 2017.
An Afghan soldier has opened fire on American troops, wounding at least seven of them, before being shot dead in a military base in northern Afghanistan, officials said, in the second so-called "insider attack" in the past week.
Seven US soldiers were injured yesterday in an insider attack by an Afghan soldier who turned his weapon on his instructors and advisers. A second report done in 2011 by US military psychologists and behavioral scientists, who interviewed dozens of Afghan and American soldiers, discovered a dramatic cultural disconnect, with most Afghan soldiers feeling mistreated and insulted by their American allies.
Taliban spokesman Zabihullah Mujahid praised the attack in a statement sent to the media.
US President Donald Trump is learned to have delegated authority on the number of troops in Afghanistan to Defense Secretary Jim Mattis.