Police on Wednesday launched an investigation into a suspected case of arson, after a noise barrier along a road in Tsuen Wan caught fire. Emergency personnel were called to Cheung Pei Shan Road near Shek Wai Kok Estate when the force received multiple fire reports at about 11am. Firefighters took about half an hour to put out the flames. A woman, in her 70s, reported that she felt unwell after inhaling smoke. The force said authorities were treating the case as arson after finding the blaze "suspicious". The fire forced parts of Cheung Pei Shan Road to close, with motorists advised to use alternative routes.