Boy, 15, missing from Colne
He is described as white, 5ft 6in tall, slim build with short dark brown hair. He was last seen wearing a blue Jack Jones t-shirt, a blue and red Nike tracksuit top and navy blue tracksuit bottoms.
Officers are appealing to Luke, or anyone who has seen him or has any information about where he might be, to contact them.
Anyone with information can call police on 101 quoting log 1073 of 1st September.