A suicide attack on an office of the Afghan Voice news agency and a neighbouring cultural centre in Kabul has killed at least 40 people.
Another 30 were reportedly wounded in the blast on Thursday, the Interior Ministry said.
The attack occurred during a morning panel discussion on the 38th anniversary of the Soviet invasion of Afghanistan at the Tibian Social and Cultural Centre. Many of the victims were students, according to witnesses.
Interior Ministry spokesperson Najib Danish said an unknown number of suicide attackers set off an explosion outside the centre before storming it.
They then set off explosive devices in the basement of the building where scores of people had gathered to mark the 1979 invasion.
Sayed Abbas Hussaini, a journalist at the agency, said there appeared to have been more than one explosion during the attack, following an initial blast at the entrance to the compound. He said one reporter at the agency had been killed and one injured.
Photographs sent by witnesses showed what appeared to be serious damage at the site, in a heavily Shia Muslim area in the west of the capital, and a number of dead and wounded on the ground.
Afghan Voice has Shi'ite links but there was no immediate claim of responsibility. Taliban spokesman Zabihullah Mujahid issued a statement on Twitter denying involvement.
The attack, the latest in a series to hit Afghan media groups in recent years, follows an attack on a private television station in Kabul last month.
Backed by the heaviest US air strikes since the height of the international combat mission in Afghanistan, Afghan forces have forced the Taliban back in many areas and prevented any major urban centre from falling into the hands of insurgents.
But high-profile attacks in the big cities have continued as militants have looked for other ways to make an impact and undermine confidence in security.
According to a report this month by media freedom group Reporters without Borders, Afghanistan is among the world's most dangerous countries for media workers with two journalists and five media assistants killed doing their jobs in 2017, before Thursday's attack.
Separately, Dawlat Abad District Gov. Mohammad Karim said a powerful mine killed six shepherd children ranging in age from eight to 10 on Wednesday.
No one immediately took responsibility for the attack, but Karim blamed the Taliban, saying the insurgents planted the mine to target Afghan officials and security forces.
Afghanistan has the highest number of mine victims in the world, which along with other roadside bombs, kill or wound an estimated 140 people every month.
Elsewhere, a Taliban attack on a security police post in central Ghazni province Wednesday night left three police dead and one other wounded, said Mohammad Zaman, provincial chief of police.
Additional reporting by agencies
