|Nigeria, an oil-rich nation of 150 million, typically has strong seasonal rains that wash through the country [File: EPA]
Almost half of the population in Nigeria's central-northern Jigawa state has been displaced after authorities had to open floodgates on two swollen rivers.
"We have about two million people affected," in a state which has 4.3 million people, Umar Kyari, the spokesman of Jigawa state, said on Friday.
He said the flooding was caused after authorities opened floodgates of the Challawa and Tiga dams in neighbouring Kano state to avoid overflowing following heavy rains.
"When the rains became too much they realised the water was too much and opened the dams," Kyari told AFP news agency from Dutse, the capital of Jigawa state.
"Over 5,000 villages in 11 of our 27 local government areas were affected. It started more than two months ago and it's continuing as I speak," he said.
Aminu Mohammed, the state information commissioner, said local officials had begun putting displaced families in rural schoolhouses and other government buildings out of the reach of the flood waters.
"The flood has washed away all the farms and houses," he said.
Flood waters have submerged about 90,000 hectares [222,400 acres] of farmland with food and livestock estimated at 4.5bn naira [$30m] destroyed.
Seyi Soremekun, a spokesman for the Nigerian Red Cross, said volunteers had already reached Jigawa and Sokoto states to offer assistance.
"I think the most pressing need is how to put the victims, those affected, in shelter from the harsh weather," Soremekun said.
"They need blankets; they need some personal effects to at least deal with or absorb the shock of displacement."
Kyari said that although the floodgates are opened almost every year to avoid overflowing and waters wash away villages on the low-lying plains of the state, "this year is just very bad".
Nigeria, an oil-rich nation of 150 million in West Africa, typically has strong seasonal rains that wash through the country. However, this year has seen particularly strong rains that already broke a dam and flowed over levees in another northern state.