It was intended to be the photograph that settled the matter once and for all — three months after vanishing from public view, and after reports that he had undergone brain surgery following a stroke, the North Korean leader, Kim Jong Il, was alive and well.

But a close look reveals something shady around the ankles of the world’s last Cold War dictator.

While the legs of his soldiers cast a shadow at a sharp angle, the shadow of the “Dear Leader” is dead straight. In addition, there is a black line running horizontally behind the soldiers’ legs, but it mysteriously disappears behind Mr Kim.

Rather than a genuine photograph, there were growing suspicions last night that the image released by the North Korean authorities may possibly be the result of digital trickery. Yesterday the state-controlled North Korean media announced that Mr Kim had attended a musical performance at which he “waved back to the cheering performers and congratulated them on their presentation”. The photographs were first presented the day before — and together they eroded the consensus among North Korea watchers that the leader of the world’s most unpredictable nuclear power had suffered a serious health problem over the past few months.

The pictures show Mr Kim posing for a group photograph with a military unit, wearing a light coloured winter coat, sunglasses and sporting his familiar pompadour. On Sunday, in similarly undated photographs, he was shown apparently attending a football match.

“He expressed expectation and conviction that all the artistes would conduct dynamic revolutionary art activities in the future too, to powerfully encourage the army and people in the drive for accomplishing the cause of building a great prosperous powerful nation,” said yesterday’s report on KCNA.

Mr Kim ceased making public appearances in mid-August but it was only on September 9 that his absence from view became a matter of pressing concern. That was the 60th anniversary of the North Korean state, a day of almost sacred significance, when parades and celebrations were held all over the country. Despite attending the 50th and 55th anniversaries, Mr Kim failed to appear.

There was speculation that he was ill or had even died — an alarming possibility in a country with a million-strong army, nuclear weapons technology, a hungry population and no formal system of succession. The head of the South Korea spy agency, Kim Sung Ho, publicly confirmed media reports from unnamed US intelligence sources that Mr Kim had suffered a stroke and been treated by foreign doctors.

“Although he is not in a state to walk around, he is conscious,” he told South Korean MPs. “We understand that he can control the situation and he is not in an unstable condition.”

If the recent photographs are genuine, then he has made a remarkable recovery — or reports of his indisposition have been greatly exaggerated. It is a big if — and there has been much poring over other images for signs of fraud or fakery. Pictures released last month, for example, were dismissed because the state of the foliage in the background suggested that they had been taken in summer — probably before the alleged stroke.

In the photographs at the football match Mr Kim is not making great use of his left arm, leading to speculation that he was suffering partial paralysis. In the latest pictures of the military, he is seen to be clapping and raising both hands.

North Korea analysts suggested that the release of the news was timed deliberately to coincide with the election of Barack Obama. “He’s sending a message to the US,” says Moon Chung In, a professor at Seoul’s Yonsei University, who has twice met Mr Kim in Pyongyang. “They’re saying our leader is alive and well, and we’re ready to talk.”sity, who has twice net Mr Kim in Pyongyang. “They’re saying our leader is alive and well, and we’re ready to talk.”

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