Five employees of the ministry of mines and petroleum were killed and 10 wounded in the bus attack, the officials said, adding that seven people were killed and more than 20 wounded in the second explosion.
Afghan security forces are facing almost daily attacks by Taliban militants, despite reported progress in efforts by the United States to broker an end to Afghanistan's nearly 18-year war.
A powerful bomb blast outside the gates of Kabul University in the Afghan capital on Friday killed at least eight people and wounded 33, as students and lawyers waited to take an examination, officials said.
The rush-hour explosion sent a plume of smoke into the air above the Puli Mahmood Khan neighbourhood of the Afghan capital and shook buildings up to two kilometres (1.2 miles) away, with the media reporter saying he could hear gunshots after the blast.
The violence came on the first day of campaigning for the upcoming presidential elections, serving as a grim reminder of Afghanistan's woeful security situation and the sort of mayhem and murder that have beset previous polls.
Health ministry spokesman Wahidullah Mayar said at least 95 people, mostly civilians and including women and children, had been taken to hospital.
The bloodshed in the capital comes amid an ongoing surge in attacks across Afghanistan, where some 1,500 people were killed or injured last month alone.
Daesh said one of its fighters blew himself up at a "large gathering" in Kabul while others "detonated a parked explosives-laden vehicle" when security forces arrived, in a statement posted on the Telegram messaging app.
Deadly violence has been taking a heavy toll on civilians in Afghanistan despite the ongoing peace negotiations and that’s not acceptable. The UN Assistance Mission in Afghanistan (UNAMA) has in its latest report stated that more civilians were killed by Afghan and international coalition forces in the first half of this
It was a heartless and condemnable act of terrorism in Kabul in which several people died and many were injured (“Bomb targets Kabul University, several die,” July 20, Gulf Today). There should be an end to war and terrorism in Afghanistan. For many decades the innocent Afghan people are being victimised