A Bangladeshi military training aircraft crashed into the campus of a school in Dhaka, killing the pilot and at least 19 others, mostly students, officials say.

More than 170 people were injured after the training aircraft crashed, military officials said. The country’s interim leader called the loss “irreparable.”

Hundreds of students gathered outside the smouldering remains of a school in the Bangladeshi capital on Tuesday to demand answers after a military jet slammed into the campus, killing dozens of children.