A specialist ship is to be used in the search for two missing fishermen and their boat off the coast of Lewis.

Norman "Tam" Murray, 40 and Murdo Morrison, 23, were on board the Kilda when it disappeared on 13 October.

The body of crewmate Douglas Craigie, 49, was recovered from the sea in the early hours of the following morning by rescuers.

Police Scotland said Northern Lighthouse Board's ship, NLV Pharos, was being brought it. The vessel has hydrographic and wreck survey equipment.

Items belonging to the fishing boat were recovered during the search last week.

Insp Neil Taylor said the effort would continue with help from the Marine Accident Investigation Branch, coastguard and local maritime experts.

He said: "It is imperative we get answers for everyone involved and please be assured our efforts are continuing.

"We would urge people not to put themselves at any risk.

"Please do not attempt to carry out searches in areas which put you at risk of harm."