ALGIERS, Algeria (AP) - Algerian officials say 20 of the 41 foreign hostages being held by Islamist militants in Algeria have escaped. Some of those who got away are Americans.

The militants have been holding the foreigners hostage deep in the Sahara desert. They say it's in revenge for Algeria's support of French efforts to remove Islamists from control of neighboring northern Mali.

An Algerian security official says that Islamist militants attacked a BP facility in the south of the country, kidnapping at least eight foreigners, including English, Norwegian and Japanese nationals.

The official, based in the south, said Wednesday that the attack came at 2 a.m and the militants came from Mali.

The Algerian army has since caught up with them and surrounded militants and their hostages, the official said.

The official, who spoke on condition of anonymity because he was not authorized to speak to the press, said negotiations between the army and militants were ongoing.

In a statement Wednesday, BP confirmed there had been a "security incident this morning" at their In Amenas gas field in east central Algeria, some 60 miles from the Libyan border.

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