A man who has yet to be identified fell into the lagoon from the Lekki-Ikoyi link bridge in Lagos state.
The event occurred on Tuesday afternoon, according to reports.
The fatality, according to witnesses, was a dispatch rider who left his operable motorcycle on the bridge before jumping into the Lagoon.
When he parked on the bridge, hawkers and pedestrians who saw him before the event assumed he was fixing his bike.
Rescue attempts are presently underway at the scene, which has been blocked off by police.
The incident was confirmed by Lagos police spokesperson Benjamin Hundeyin in a tweet.
Hundeyin stated that police officers were on the site managing the crowd while the rescue mission worked to get the victims out.
