Thursday's Russian press continue to speculate over the disappearance, and subsequent reappearance, of presidential candidate Ivan Rybkin.

Some papers conclude that the whole affair was a publicity stunt gone wrong while others look for darker reasons to explain Mr Rybkin's absence.

An article in the popular daily Trud pokes fun at Mr Rybkin's decision to, as the writer puts it, "rest incognito in Kiev".

"Well, well," it smirks, "he hasn't been elected to anything yet, he hasn't taken on a particularly heavy workload - and already, he's exhausted."

It criticises Mr Rybkin, saying his behaviour was "to put it mildly, inappropriate".

And it attributes his disappearance to a "clumsy attempt to draw attention to himself by any means possible - regardless of what kind of attention that may be".

An article in the mass-circulation Moskovsky Komsomolets labels Mr Rybkin's disappearance a "bad joke" and shares Trud's view that the whole episode is little more than a PR exercise.

"Just a week ago, even a local hack wouldn't have been interested in Rybkin. Now look: excitement and a media scrum," the paper observes.

But this is not the sort of publicity Mr Rybkin would have been looking for.

"I couldn't shake the feeling that this was a farce in a provincial theatre," adds the article.

Open to question

Elsewhere on its pages, Moskovsky Komsomolets argues that whatever Mr Rybkin has been doing, the last few days have not helped his cause.

"Either he got drunk or spent time with a mistress. Or somebody picked him up, threatened him, tortured him and let him go," the paper suggests. "Or he set it all up to raise his popularity."

Either way, the paper says, "the end result looks shameful".

Government daily Rossiskaya Gazeta agrees there are still a number of questions that need answering.

"The question of where Mr Rybkin was and what he was doing remains open," the paper says.

"Nobody can say for certain that Mr Rybkin was in Kiev," it maintains.

"Even the staff of the Hotel Ukraine, where he was allegedly staying, knew nothing of his presence."

An article in the Nezavisimaya Gazeta broadsheet questions whether Mr Rybkin's disappearance was truly without sinister overtones.

"If Ivan Rybkin were voluntarily in the Ukrainian capital, he could not have failed to know that he was being looked for in Russia," the paper reasons.

"Is it believable that none of these mythical friends whom Rybkin allegedly came to visit ever watched the news or thought it appropriate to bring to his attention the fact that he was being searched for?"

The leading daily Izvestia also takes a sceptical view of Mr Rybkin's explanations for his absence.

While he was in Kiev, the paper says, he told his wife that he "had passed the time pleasantly". But by the time he had returned to Moscow, his story appeared to have changed.

"He told journalists something entirely different - a few phrases reminiscent of charades, from which it could be deduced that the Kiev weekend went far from smoothly," the paper says.

Disappearing act

Popular tabloid Komsomolskaya Pravda, meanwhile, uses the story to draw conclusions about the state of Russian politics.

"By evaporating in the Kiev haze, Mr Rybkin has shown the way to all of his 1990s liberals," the paper notes. "Disappear - that's a well-chosen word."

Russian liberalism, the paper laments, seems to be vanishing from the political landscape.

"And we who are left are doomed to remain in this authoritarian and airless Russia," the paper concludes.

BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.