Thirty-five children have died during a stampede at a school fair in southwestern Nigeria, authorities said.

Nigerian President Bola Tinubu on Thursday expressed his "profound sadness over the tragic incident" and offered his condolences to the families of the victims. 

What do we know about the stampede?

The stampede occurred Wednesday at the Islamic High School in Basorun, Oyo State, near the economic hub of Lagos.

At least six others were injured in the crush, according to Osifeso Adewale, a police spokesperson.

State Governor Seyi Makinde called it a "sad day."

Thousands of people had gathered at the school for an event organized for families.

Police officials said they believed that the surge began after event organizers began distributing food and gifts.

Several people, including the principal of the school, have been detained. According to media reports, the police arrested a former queen of the Ooni of Ife, Prophetess Naomi Silekunola, as part of investigations into the stampede.

The event was organized by Women in Need of Guidance and Support, a non-governmental organization founded by Silekunola.

Nigeria witnesses deadly stampedes in recent months

Deadly stampedes have occurred in recent months in Nigeria.

In March, two students died and at least 23 people were injured after being crushed by a big crowd that had gathered to collect free bags of rice.

Also that month, at least four people were crushed to death at another place where they were meant to collect cash gifts that would help them pay for food.

rm/jsi (AFP, dpa, Reuters)