LONDON (Reuters) - British forces in Afghanistan deliberately destroyed one of their helicopters on Sunday after it was damaged on landing, in the second such incident in a month, the Ministry of Defence said. The four crew and 15 soldiers on board the Chinook were unharmed following a hard landing near Sangin in Helmand province that damaged the undercarriage, nose and front rotor, making the aircraft unflyable. The troops who were being transported to the area, were able to continue with their operation and the crew were picked up by another helicopter. The Ministry said there was no evidence to suggest the incident was caused by enemy action. The Chinook was later destroyed to prevent it falling into the hands of the Taliban. Earlier this month forces destroyed another British Chinook that had crashed after an engine fire. The ministry would not say how many Chinooks it had left in Afghanistan, but said NATO partners would provide short-term cover before the Chinook was replaced.