The Ministry of Interior (MOI) said the blast happened near the Sayeed-ul-Shuhada School in the Dasht-e-Barchi area on Saturday afternoon.
The explosion was caused by a car bomb followed by two IED explosions, Interior Ministry spokesman Tariq Arian said Sunday.
There has been no claim of responsibility yet.
Taliban spokesman Zabiullah Mojahid denied involvement in the explosion in a message to the media.
According to Afghanistan’s Tolo News, the incident happened when students were leaving the school. “A car bomb blast happened first, and then two more explosions occurred near the girls school in Kabul,” said Ibrahim, a schoolteacher, according to Tolo. He added that the majority of victims are girls, Tolo reports.
Violence in the country, at war for two decades, remains unacceptably high, foreign governments and institutions say, calling for an immediate ceasefire between the Afghan government and Taliban.
The National Intelligence Council assessed that the progress made over the last two decades “probably owes more to external pressure than domestic support, suggesting it would be at risk after coalition withdrawal, even without Taliban efforts to reverse it.”
Biden administration officials have warned that the Taliban would not achieve international legitimacy by seizing power by force or by limiting the rights of women.
CNN’s Radina Gigova contributed to this report.