RAIDERS smashed their way into a Steeton convenience store.
They struck at the Morrisons Local outlet, in Skipton Road, at about 1.15am on Tuesday.
The thieves – who used a paving slab to smash entry through a window – took a quantity of cigarettes, but the break-in triggered a special device which emitted a smoke deterrent.
It is believed the assailants may have escaped in a black Audi.
Police are appealing for anyone who witnessed the incident, or has any information, to come forward.
And their plea for public help is echoed by Morrisons, which opened the Steeton store just last month.
"We would urge anybody able to assist to contact the police," said a spokesman.
"The mess created by the break-in was cleared up very quickly by our staff and the store was able to open as normal that day."
The smoke-emitting device also raised an alarm with the fire service, and a crew from Keighley Fire Station was called out.
Firefighters used a special ventilation fan to clear the smoke from the premises.
Witnesses to the break-in or anyone with information should phone the police on 101 or Crimestoppers on 0800 555 111.