On 7 October 1737, a natural disaster struck the city of Calcutta (modern-day Kolkata) in India. For a long time this was believed in Europe to have been the result of an earthquake, but it is now believed to have been a tropical cyclone. Thomas Joshua Moore, the duties collector for the British East India Company in Calcutta, wrote in his official report that a storm and flood had destroyed nearly all the thatched buildings and killed 3,000 of the city's inhabitants. Other reports from merchant ships indicated an earthquake and tidal surge were to blame, destroying 20,000 ships in the harbor and killing 300,000 people. The population of Calcutta at the time was around 3,000–20,000.