(CNN) -- At least 25 people were killed in flooding that hit the city of Ibadan in southwestern Nigeria over the weekend, the Nigerian Red Cross said Tuesday.
More victims could still be found in remote areas that rescue teams have not reached, the government's National Emergency Management Agency said in a statement released Monday.
Visiting the area, the agency's chief, Alhaji Muhammad Sidi, was shocked by the devastation and said the flooding was some of the worst the country had seen in recent times, the statement said.
The government is delivering aid to people displaced by the flooding in Ibadan and surrounding areas in Oyo state, the agency said.
Thousands of people have been displaced, and about 1,500 of them are being looked after in centers run by government officials and the Red Cross in the Ibadan area, Red Cross spokesman Umar Mairiga told CNN on Tuesday.
They are being given emergency food rations, as well as mattresses, blankets and rubber mats, Mairiga said.
The deputy governor of Oyo state, Chief Moses Adeyemo, called for more federal government help to resettle those displaced and to rebuild bridges and water channels destroyed by the flooding, the statement said.
NEMA warned that there could be more flooding in urban areas during the rainy season if drains were inadequate or blocked by uncleared waste.
Alhaji Sidi has also visited some of those injured in a car bomb attack on a United Nations building in the capital, Abuja, on Friday, the agency said.
The United Nations said Sunday that 21 people had died and 73 were injured in the attack, of whom more than 20 remained in intensive care.
CNN's Christian Purefoy and Laura Smith-Spark contributed to this report.