Algeria siege: Hostages 'escape Islamist captors'
A number of hostages have escaped the Islamist militants who took them captive at a gas facility in eastern Algeria, media and officials say.
Details of the escape and the numbers involved remain unclear, but some 30-40 Algerians and 15-20 foreign nationals were reported to have escaped.
Algerian troops have surrounded the facility near In Amenas.
The kidnappers occupied the complex on Wednesday, after killing a Briton and an Algerian.
One Algerian security official told Associated Press news agency that at least 20 foreigners had escaped, including Americans and Europeans.
Algeria's private Ennahar TV channel said that 15 foreigners, including a French couple, had escaped.
Earlier, the Algeria Press Service news agency said 30 Algerian workers had also managed to free themselves.
The Tigantourine gas facility is about 40km (25 miles) south-west of In Amenas, which is close to the Libyan border and about 1,300km (800 miles) south-east of Algiers.
BP operates the gas field jointly with Algerian state oil company Sonatrach and Norwegian firm Statoil.
The companies and the governments of those taken hostage have given few details about the number and identity of those taken captive, citing security reasons.