JAKARTA: Indonesian President Susilo Bambang Yudhoyono's leadership has been called into question after the rattled leader appeared to link political rivals with the deadly suicide bombings in Jakarta.

Critics have denounced as an "excessive rant" a teary speech by Yudhoyono after Friday's attacks, when he suggested the bombings could be linked to alleged plots by rivals to overturn his re-election the week before.

But supporters say the normally taciturn president may have evidence to back up his claim or at least be making a sophisticated ploy to shut down elements of the political and military elite with dark pasts and high ambitions.

Hours after the attacks on the JW Marriott and Ritz-Carlton hotels killed seven people -- widely suspected to be the work of Islamist extremists -- Yudhoyono made an emotional address to the nation.

He denounced the attackers as "Draculas and spreaders of death" and appeared visibly upset as he described plots to violently overturn the July 8 polls, which he won with over 60 percent of the vote.

"This morning I heard from several parties who have an unsettling theory that this terror act is related to the presidential election," he said.

He dramatically held up a photograph of himself which he said had been used as target practice by a "terrorist group".

"There are video recordings and pictures. This is not slander, this is not a rumour," he said.

"There are likely those among us who in the past have carried out crimes, murdered, made people disappear, and these perpetrators have maybe been able to slip away from the reach of the law," he said.

Analysts have been left scratching their heads about what exactly the usually uncontroversial president was talking about.

Yudhoyono's performance was an "excessive rant" that bore "shades of a despotic regime bent on blacklisting political opponents through espionage," The Jakarta Post daily said in a damning editorial Tuesday.

"We saw another side of the soon-to-be-confirmed president-elect. A side that was unnecessarily menacing. A side that the nation need not see again," the Post said.

Yudhoyono's defeated election opponents have taken it personally.

The president's comments were an attempt to "scapegoat other candidates" who had complained of poll irregularities, Sony Keraf, a spokesman for the defeated campaign of Megawati Sukarnoputri, told AFP.

Megawati's team has alleged widespread irregularities in the poll and has threatened to challenge the results, which still have not been officially released.

"I think (the speech) seems to be a sign from him that nobody should complain about problems in the election," Keraf said.

While Yudhoyono did not name names -- and was sure to pepper his speech with caveats -- observers say it was obviously aimed at Megawati's running mate, ex-special forces commander Prabowo Subianto.

Prabowo has made a stunning political comeback and is widely considered a top contender for the presidency in 2014 despite persistent accusations of rights abuses -- including the disappearance of pro-democracy activists -- as a loyal general under ex-dictator Suharto.

Many liberals are scared a Prabowo presidency could strangle Indonesia's democratic transformation.

Yudhoyono's televised address after the attacks was a way of "telling Prabowo to shut up" over voting irregularities, political analyst Wimar Witoelar said.

He alleged it was not impossible that Prabowo -- who is accused of manipulating shadowy irregular forces to foment violence in East Timor and Jakarta in the past -- had a hand in the attacks.

"We know that bombs in Indonesia... have many fathers. There are a lot of people with an interest in unrest," he said.

Presidential spokesman Andi Mallarangeng defended his boss.

"The president didn't mention any names, the president even warned people not to accuse anyone right now," he said.

"But you should not disregard any clues, any intelligence reports, any evidence, even preliminary evidence."