荃灣西約
At 9:15am on 14 February 2007, a passenger train broke down when one of the voltage transformers mounted on the train roof exploded. This incident occurred in the southbound direction in the tunnel between Kam Sheung Road and Tsuen Wan West, about north of Tsuen Wan West. Around 650 passengers had to evacuate through the dark tunnel to the station, while around 340 people returned to the ground through a ventilation shaft at Chai Wan Kok. Eleven people were sent to hospital. Train services returned to normal after 4 hours.