At least six people were killed and 11 others injured in three explosions that rocked a high school in the Shiite Hazara neighborhood of Afghanistan's capital, Kabul, security and health officials said on Tuesday.

"Three blasts have taken place ... in a high school, there are some casualties to our Shiite people," said Khalid Zadran, the spokesperson for Kabul's commander.

He said later that six people had been killed and 11 injured in the explosions.

The head of a hospital nursing department, who declined to be named, said at least four people had been killed and 14 wounded in the blasts.

Another medical center, Emergency Hospital, said it had received one dead body and 10 teenagers injured in the explosions.

Interior Ministry spokesperson Abdul Nafay Takoor told Deutsche Presse-Agentur (dpa) that the blasts targeted Abdul Raheem Shaheed School, which is located in the city's police district 18. He said an investigation was under way and details will be shared later. Another security official said that the blasts were caused by hand grenades.

Tuesday's blasts occurred as students were coming out of their morning classes, a witness told Agence France-Presse (AFP).

There was no immediate claim of responsibility for the attack, which followed a lull in violence over the cold winter months and after foreign forces withdrew last year.

Western Kabul has witnessed numerous deadly attacks in the past. The Taliban say they have secured the country since taking power in August, but international officials and analysts say that the risk of a resurgence in militancy remains and Daesh terrorist group has claimed several major attacks.

In May 2021, bombings near a school in the Dasht-e-Barchi area of Kabul killed at least 85 civilians, mainly schoolgirls, and injured dozens of others.