Hong Kong police have arrested a van driver after his vehicle collided with a taxi on a highway, killing two passengers, an off-duty firefighter and his wife. The Fire Services Department said on Wednesday it was “deeply saddened” by the deaths of the 38-year-old from Kwun Tong Fire Station and his 35-year-old wife. The department extended its “deepest condolences” to their families and said it would offer help where possible.