Thirty-seven youths were killed in a stampede overnight during an army recruitment drive in a stadium in Brazzaville, the capital of the Republic of Congo, according to officials.

Last week, the army in the central African nation also known as Congo-Brazzaville, announced it was recruiting 1,500 people aged between 18 and 25.

Prime Minister Anatole Collinet Makosso said 37 people had been killed in the "tragedy," with an unspecified number of other people injured. 

"A crisis unit has been set up under the authority of the prime minister," a statement added. 

Would-be recruits had been directed to go to the Michel d'Ornano stadium in the heart of Brazzaville. 

According to local residents, many people were still in the stadium on Monday night when the stampede began. 

Some people had tried to force their way through gates, with many being trampled in the scramble, residents said.