A 21-story building in Lagos, Nigeria, collapsed on Monday, and dozens are feared trapped, reports CNN. The building was in the Ikoyi neighborhood, an affluent area known for luxury apartments. According to Olu Apata, a nearby resident and president of the Nigerian Bar Association, the building has been under construction for two years. “I thought it was an earthquake when I rushed out of my apartment just after 3 p.m.,” said Apata. “I felt the building move and knew something was wrong.” Hundreds of people were seen rummaging through the rubble in an attempt to rescue those in the building. Passerby Rashid Olamilekan allegedly had to pull three construction workers out from the slabs of concrete. After a long delay, the Nigerian Red Cross has begun to assist with the collapse, which was not an anomaly; one expert told CNN that over 1,000 buildings could potentially collapse in Lagos.