Three girls aged between seven and 10 have drowned in River Oluwa, Sabo area of Ondo town, Ondo West local government area.
Names of the victims were given as Iyabo Isiaka, Nife Akinnuoye and Seun Segun.
The incident was said to have happened on Friday.
They were said to have fallen off a bridge in the river and got drowned.
Sources said the deceased teenagers went to the river to play and swim.
Divers that rushed to save the children were late as they found their lifeless bodies floating on the river.
Another source said nobody was aware of the incident until a boy saw one of the victims floating in the river.
The deceased children have been buried by their parents.
Ondo Police spokesman, ASP Tee-Leo Ikoro, confirmed the incident and said the children fell off a bridge.