DHAKA -- The death toll from the crash of a Bangladesh Air Force training aircraft on a school and college campus on Monday has risen to 27, with 25 of the victims being children.

The other two victims include the aircraft's pilot and a female schoolteacher, Md Sayedur Rahman, special assistant for health and family welfare for the chief adviser of the interim government, said at a press briefing here Tuesday.

At least 78 people are undergoing treatment at different hospitals and five of them are in critical condition, Sayedur said.

The government has announced a one-day national mourning to be observed on Tuesday in response to the tragic incident. On the day, the national flag will be flown at half-mast across all government, semi-government, autonomous bodies, educational institutions, and private organizations throughout the country, as well as at Bangladeshi missions overseas.

According to the Inter Services Public Relations Directorate, a Bangladesh Air Force aircraft involved in a routine training flight took off from the A.K. Khandaker Air Base in Kurmitola, Dhaka, at 1:06 pm local time on Monday and crashed shortly later into a two-storey school building.