Police and witnesses said a boat carrying 29 people capsized in the Tafa River, Maun 2 in the Ipokia district of Ogun State, killing 11 people.
Two people were missing, the police said.
The Premium Times reports that the accident took place on Thursday night, but the news did not appear until Saturday.
A witness suggested that the cause of the accident was an engine problem.
He said the boat was in the middle of the river with passengers and goods from Badagry in Lagos to Maun in Ipokia when the accident occurred.
The Ogun State Police spokesman, Abimbola Oyeyemi, made the incident "congestion."
He also said that the boat drove without lights at night, and collided with a pillar in the river.
"Yes, boat had capsized, it was overloaded" he said. "The boat had no light and traveled at night. It had a frontal collision with a pillar in the river. The passengers came from Badagry in Lagos to Ipokia. "
Mr. Oyeyemi said the boat had been the last for the night and all 29 dealers got in.
"Sixteen were rescued alive, ten yesterday yesterday (Thursday night) and one died on Friday. No live jacket. There were marines on the ground. Two are missing. Skipper arrested after he ran away " he said.
He added that the police commissioner Ahmed Iliyasu had ordered that the division police officer should ensure that the boats have jackets.
At the time of depositing these reports, remnants of the deceased had been deposited in the morgue in Ipokia.