"I was in my office when I heard a big blast", another employee told AFP.
The explosion took place when employees were leaving their offices early for Ramadan.
An Afghan policeman keeps watch near the site of a suicide attack in Kabul, Afghanistan June 11, 2018. "We are told to stay inside for now".
Taliban fighters have killed a district governor in northern Afghanistan while clashes are ongoing elsewhere, despite the start of a government ceasefire, officials said.
The attack, which IS claimed via their Amaq propaganda agency, killed 13 people and wounded 31, said Mr. Azhand. Security forces seized a vehicle loaded with explosives outside the building, said the spokesperson for Attullah Khogyani, the governor of Nangarhar. At least 10 people were wounded, said city health department director Najibullah Kamawal.
The Taliban militants have launched a coordinated attack on Moqor district in southeastern Ghazni province of Afghanistan on the first day of the cesaefire announced by the Afghan government.
In another incident, an explosion inside a house in Kabul killed one person and wounded three others, Stanikzai said.
A spokesman for the provincial governor blamed the Taliban, which recently declared a temporary ceasefire until the end of the Eid Muslim holiday.
The militants have also said their ceasefire does not extend to US-led North Atlantic Treaty Organisation forces, while Kabul said operations against foreign fighters including the Islamic State group will continue.
Talking to Commander RSM, the COAS said that Pakistan desires that US/ NATO forces must succeed and leave behind a peaceful and stable Afghanistan, the ISPR mentioned.
Afghan security forces and the Taliban have vowed to retaliate if attacked during the ceasefire.
It is the first time the militants have agreed to suspend fighting since the 2001 United States invasion, and the move was largely welcomed by war-weary Afghans.
The violence occurred just before the government is due to begin a week-long truce with Taliban insurgents Tuesday.