The whole of the Western Isles has gone into lockdown as part of efforts to stem the spread of coronavirus.
The region moved into the toughest tier of Covid-19 restrictions at midnight on Saturday following a spike in cases.
Barra and Vatersay had already been moved from level three to level four following a separate outbreak earlier in the month.
At the Scottish Government’s daily Covid briefing on Friday, health secretary Jeane Freeman said six new cases were reported in the Western Isles on Friday and nine on Thursday.
As a result of the spikes, the Western Isles Hospital in Stornoway has reached capacity.
Although some non-urgent procedures will be rescheduled, the hospital is expected to maintain a full emergency service.
Freeman said: “When the situation demands it, we must act quickly and decisively to safeguard health, save lives and protect the NHS.
“As we said we would, we have kept the island areas under review.
“The advice of our clinical advisers is that due to a rising trend of infections, lockdown is now necessary in the Western Isles.
“Discussions are under way to offer support and ease the pressure on local health services.
“It is essential that we further limit interaction between different households to stem the spread and bring the situation back under control, while we vaccinate more people.”
The Western Isles now join the whole of mainland Scotland, as well as Skye, under the ‘stay at home’ restrictions where schools, non-essential shops, gyms, salons and most hospitality venues remain closed.
Council leader Roddie Mackay said: “The designation of the Western Isles as a level four Covid-19 area is disappointing but not entirely unexpected given the recent rise in cases and the developing situation at the Western Isles Hospital in Stornoway.
“Our communities continue to make stringent efforts to protect themselves and others and it is imperative, now more than ever before, that we maintain and indeed – wherever possible – increase these efforts.”