Chancellor of Austria Christian Kern | Georg Hochmuth/AFP via Getty Images Austrian Chancellor Kern rocked by Facebook scandal Investigation launched after social media posts critical of country’s likely next leader.

Austrian Chancellor Christian Kern's Social Democrats (SPÖ) promised an investigation into social media posts attacking rival Sebastian Kurz, but denied knowing that they had been put online.

On Saturday, Austrian magazine Profil reported that two Facebook pages — "Die Wahrheit über Sebastian Kurz" ("The truth about Sebastian Kurz") and "Wir für Sebastian Kurz" ("We for Sebastian Kurz") — were being used to discredit the leader of the center-right People's Party (ÖVP), just two weeks ahead of a general election. Several posts on the pages insulted Kurz, including pictures and videos edited to make him look foolish.

Involved in setting up the Facebook pages, which were both taken down on Saturday, was Tal Silberstein, a former SPÖ election adviser, according to Profil. Silberstein was ditched by the party in August after he was reportedly the subject of a money-laundering investigation in Israel.

Christoph Matznetter, whom Chancellor Kern put in charge of investigating the affair, told Austrian radio show Ö1 Morgenjournal on Monday: "We woke up in the middle of a tsunami."

"This is not our style, we don't want this type of politics," Matznetter said, insisting that he and other senior party members were not aware of the Facebook pages. He promised that the results of his investigation would be published before the election on October 15, Kleine Zeitung reported.

On Saturday, Georg Niedermühlbichler, who had been on the SPÖ's executive board, resigned. The far-right Freedom Party described Niedermühlbichler as a "sacrificial lamb" and urged Kern to step down, Süddeutsche reported.

On Sunday evening, five of the leading candidates in the election took part in a live TV debate. The Facebook scandal cast a shadow over the show, with the FPÖ's Heinz-Christian Strache saying: "This is no longer a Silberstein issue. This is a Kern issue."

Kern promised "absolute clarification" on what happened.

Gute Diskussion bei #MeineWahl. Verlangen volle Aufklärung d Dirty Campaigning d #SPOE! Hier wurden Grenzen überschritten! #nrw17 pic.twitter.com/MLTzG9l2ac — Sebastian Kurz (@sebastiankurz) October 1, 2017

Kern's party has been in third place in recent polls, at 24 percent, with Kurz's ÖVP on 33 percent and the FPÖ on 26 percent.