It has long been suspected that Hakimullah Mehsud, the leader of the Pakistani Taliban, was killed in a missile strike carried out by the US in January.
But in a video that appears to have been recorded on April 4, Mehsud calls the US a "terrorist state" and says his fighters will launch attacks on the US.
The footage was released just a day after a failed car bomb attempt in New York's Times Square, which another Taliban group has claimed responsibility for.
Al Jazeera's Imran Khan reports.
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