SEOUL, South Korea — North Korea’s state-run television on Saturday broadcast a rerun of a propaganda documentary about its leader, Kim Jong-un, after deleting all footage showing his uncle, Jang Song-thaek, who South Korean intelligence officials believe was recently dismissed from all his posts.

The erasing of Mr. Jang from the documentary was the clearest sign yet that Mr. Jang, who had long been considered the second most influential man in the reclusive North Korean government, has fallen from power. In the past, when North Korea purged high-ranking officials, it destroyed the publications containing their photos or reissued them with their pictures blacked out.

The North’s Korean Central Television ran the hourlong propaganda film nine times from Oct. 7 to Oct. 28, according to the national news agency Yonhap of South Korea, which monitors the North Korean broadcasts. The documentary featured Mr. Kim’s military-related activities, such as his visits to barracks to the rousing welcome of soldiers. In a dozen spots, Mr. Jang was seen accompanying Mr. Kim.

When Korean Central Television showed a rerun of the documentary on Saturday after a 40-day hiatus, Mr. Jang was nowhere to be seen. The footage showing him was edited out or was replaced with new scenes, according to the comparisons of old and new versions shown in the South Korean news media.