Several blasts shook the Afghan capital on Tuesday, with explosions at a boys' high school leaving at least seven injured, officials said.

The explosions targeted a training center and the Abdul Rahim Shahid high school in the western Dasht-e-Barchi area of Kabul.

The children were leaving school at the time of the first blast. A second explosion hit shortly after the first. Witnesses told the Associated Press that a suicide bomber blew himself up inside the school complex that can house up to 1,000 students.

Local media reported that at least 20 people had been killed. The number given by officials was at least seven injured, but they said this number could go up.

Khalid Zadran, police spokesperson for the Taliban in Kabul, wrote on Twitter that the attack had "caused injuries to our Shiite compatriots."

He later told AFP that the attack "killed six people and wounded 11 others."

Shiite minority apparent target

Afghan news channel Tolo news said that the Ministry of Interior had confirmed the blasts at the school and had launched an investigation.

Victims of the attack were taken to hospital, but the Taliban cordoned off the area and banned journalists from taking photos.

Italian NGO Emergency — which runs a medical facility in the city — wrote on Twitter that seven children had been taken to their hospital.

Nobody has yet claimed responsibility for the attack, but western Kabul has previously been a target of the so-called "Islamic State" (IS) due to its large number of Shiite Hazara residents.

An IS attack in October 2020 on an educational center in the same area killed 24 people, including students. Another attack in May last year killed at least 85 people and injured around 300 more, mostly girl students, when three bombs went off in the Dasht-e-Barchi neighborhood.