A four-storey building collapsed in Mumbai's crowded Dongri neighbourhood this afternoon, leaving ten people dead and at least 40-50 people trapped under debris. National Disaster Response Force personnel are at the site looking for survivors. Fire trucks and ambulances are also on the spot. The area, full of dilapidated buildings on narrow lanes, was also flooded in heavy rain in the past weeks. The authorities said this was a "level 2" incident - while level 1 is the most serious under the system that measures the severity of a building collapse.