At least 29 students killed & over 250 injured in horror explosion and stampede at high school during exam

AT least 29 students have been killed and 250 injured after an explosion sparked a stampede at a high school.

Students were taking their final exams when an electrical transformer exploded in Bangui, the capital of the Central African Republic, on Wednesday.

More than 5,300 students were gathered for the second day of their national baccalaureate exams when the blast went off at Barthelemy Boganda High School.

Most of the victims, including 16 girls, died at the scene after the explosion resulted in a stampede, while others were confirmed dead in hospital, the Ministry of Health said in a statement.

The explosion happened as technicians were working to restore a faulty electrical transformer on the school grounds, according to the Ministry of Education.

Alvin Yaligao, one of the students, recalled: "The building shook and we were all terrified.

"It was everyone man for himself."

Survivors have also recalled hearing a loud explosion from the transformer midway into the exam, causing chaos to unfold.

Some of the victims died after jumping out of the building while others were killed at the crowded entrance to the upper floors in an attempt to escape.

Others fainted amid the chaos and were rushed to hospital, some of them on motorbikes.

Authorities believe panic from the blast triggered a stampede, causing most of the fatalities and injuries. 

Emergency responders scrambled to the scene and took the injured to nearby hospitals.

The blast has sparked anger among locals who accused the government of negligence for not handling the problems with the electrical transformer.

Government officials and workers who arrived at the scene were pelted with different objects by furious residents.

President of the school's parents' association, Gdon Cyr Ngass, has called for an investigation into the tragedy.

He added: "We deplore this incident which was caused by a lack of maintenance."

President Faustin-Archange Touadéra has declared a period of national mourning. 

Investigators are currently working to determine the precise cause of the explosion and whether any safety protocols were breached.