Taliban suicide bombers killed six people, during a siege in a police building in eastern Afghanistan on Sunday, officials said, the latest in a series of high-profile attacks.
Four insurgents wearing explosive-packed suicide vests were holed up inside a police building in the eastern city of Khost, near the Pakistan border, for several hours before the siege was brought to an end when Afghan troops stormed the building.
Afghan President Hamid Karzai condemned the attack in which three policemen, two Afghan soldiers and a gardener were killed. At least two explosions and gunfire were heard soon after the attack was launched.
Violence has risen across Afghanistan in recent weeks since the Taliban announced the start of their "spring offensive" with attacks against supposedly secure targets across the country.
In Kabul, a suicide bomber killed six medical students in an attack inside the cafeteria of the main military hospital in a heavily guarded area of the capital on Saturday. More than 20 were wounded. US commanders had also warned of a rise in violence this month as the Taliban try to push back against military gains against insurgents in the south over the past 18 months.
Abdul Jabar Naeemi, the governor of Khost province, said two of the suicide bombers blew themselves up during the siege and the others two were shot dead before they could detonate their explosives.
The attack was launched in the traffic control centre in a police compound in the centre of Khost city, although fighting tailed off several hours later as security forces surrounded the building.
Khost police chief Abdul Hakim Esaaqzai said the attackers were wearing border police uniforms. He said Afghan troops had entered the building to bring the siege to an end.
Television pictures showed at least one building on fire as Afghan soldiers skirted beneath a high wall on the outside of the compound. A car packed with explosives was found near the building and was being taken away to be defused, Interior Ministry spokesman Zemari Bashary said. The violence has surged as US and Nato forces prepare to begin a gradual troop drawdown and handover of security responsibility to Afghans from July.