South Korea on Sunday dismissed reports that recently-released photographs of Kim Jong-Il may have been doctored, amid continued speculation over the North Korean leader`s health.

Pyongyang on Wednesday released a still photo of Kim at the front of a military lineup in its latest effort to quell rumours that the 66-year-old had suffered a stroke in mid-August.

The London-based The Times newspaper and national broadcaster the BBC questioned the authenticity of the image, citing differently-angled shadows and mismatching pixels.

But Seoul`s main spy agency, the National Intelligence Service (NIS), said on Sunday that it believed the latest North Korean photo was real.

`The possibility of Mr. Kim`s photo being forged seems very low,` an NIS spokesman told AFP, refusing to elaborate. He declined to comment on questions raised by the British media about the photograph.

The South`s unification ministry spokesman Kim Ho-Nyoun also told AFP he had no evidence to suggest that the photo had been forged.

`From the observation with our naked eyes, we have found nothing unusual,` the spokesman said.

North Korea has not said when the recently-released photographs of Kim were taken.

Kim`s health is the subject of intense speculation because he has not publicly nominated a successor -- as his father had done more than 20 years before his death in 1994 -- to run the impoverished, nuclear-armed state.

After he failed to attend a September 9 parade marking the country`s 60th anniversary, South Korean and US officials said Kim suffered a stroke around mid-August but was recovering well.

Japan`s Prime Minister Taro Aso said last week Kim was probably in hospital but still capable of making decisions.

But some reports said Kim may have suffered partial paralysis from his stroke.

Giving new life to speculation about Kim`s health, the Times newspaper on Friday suggested the Wednesday-released photo might have been doctored.

In the photo, the shadow of Kim runs differently from those of soldiers on either side of him, The Times said, adding a dark line running along the stand mysteriously vanishes on either side of Kim -- suggesting his picture may have been superimposed onto the image.

The BBC also said it found an apparent mismatch of pixels in the photo.