For some years the nationalist movement Flec (Front for the Liberation of the Enclave of Cabinda) has been trying to claim independence from the Angolan government.

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An armed wing of a separatist group -- the Forces for Liberation of the State of Cabinda (FLEC) -- claimed responsibility for the attack and has threatened to strike again.

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The head of Flec-Position Militar (Military Position), the faction which says it carried out the attack, told the BBC it was fighting what he called Angola's illegal occupation of Cabinda.

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"It is very sad for us as well because Flec isn't about killing foreigners, but Cabinda is at war despite the lies about this by the Angolan government, " Rodriguez Mingas told the BBC's Portuguese service.

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Flec had made some veiled threats that it might attack during the Cup of Nations - when it knew the world's media would be watching - but the Angolan government gave assurances security was in place and there would be no trouble.

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