Britons have been warned not to travel to an area of Burkina Faso after a deadly attack by suspected Islamic terrorists on a hotel that is popular with Westerners.
Foreign Secretary Philip Hammond condemned the "appalling attack" in the west African country's capital, Ouagadougou.
Masked gunmen stormed the four-star Splendid Hotel, popular with United Nations staff and Westerners, on Friday evening. Communications minister Remis Dandjinou said 30 hostages, including public works minister Clement Sawadogo, were later freed from the hotel by security forces backed by French troops.
Mr Hammond said: "I utterly condemn the appalling attack in Ouagadougou last night and offer my deepest condolences to the families and loved ones of those who have been killed and injured.
"The United Kingdom stands with President (Roch Marc) Kabore and the people of Burkina Faso in the fight against terrorism.
"We advise British nationals in Burkina Faso to avoid the area where the attack took place, follow the instructions of local security authorities and monitor Foreign Office (FCO) travel advice."
The FCO warned against travelling north of the town of Boulsa, as it is near to the border with Mali. The FCO advice states: "You should avoid the area and follow the instructions of local security authorities."
Four extremists have been killed by security forces and more than 126 people were freed after a luxury hotel in Burkina Faso was seized by al Qaida-linked militants.
In addition to the four jihadis, at least 23 people were killed in the attack.
Hospital chiefs said that one survivor estimated that as many as 20 were dead inside the hotel while 10 bodies were found inside the neighbouring Cappuccino Cafe which was also attacked.
Commandos later used explosives to storm the 147-room hotel as other security forces tried to remove casualties.
The local al Qaida affiliate known as AQIM claimed responsibility online, according to the SITE Intelligence Group.
A failed military coup was staged in the largely Muslim country on September 16 and presidential and parliamentary elections which were held on November 29.
The FCO states: "There could be unannounced demonstrations and strikes and the security situation may deteriorate. You should remain vigilant and stay away from large public gatherings. The airport and land borders may be subject to closure at short notice. Monitor local media and check with your airline for more information."
In a message posted in Arabic on the militants' Muslim Africa Telegram account, AQIM said fighters "broke into a restaurant of one of the biggest hotels in the capital of Burkina Faso, and are now entrenched and the clashes are continuing with the enemies of the religion".