Seoul, South Korea ? North Korea criticized CNN for airing footage purporting to show a public execution, accusing it of being part of a U.S. government-organized slander campaign.

Earlier this month, CNN aired a documentary with footage defectors claimed to have smuggled out of the North, including a public execution of a person who had helped someone defect to China. The network had said North Korea declined to respond to a request for comment.

In commentary by its official Korean Central News Agency, the North said the footage was “full of sheer lies” and accused CNN of airing the tape at the instigation of the U.S. government as part of an alleged psychological campaign to overthrow the regime.

As part of nuclear talks seeking to convince the North to disarm, Washington has repeatedly assured Pyongyang it recognizes its sovereignty. In a breakthrough agreement at those negotiations in September, the U.S. also offered security guarantees and normalization of relations if the North abandons its nuclear programs.

The North alleged that the recent report showed Washington was hiding its true intentions.