"Seeing the results of the municipal elections, I am officially announcing that I'm laying down my MP mandate. Good luck to you, Latvia. I tried from all my heart. Really. You made the choice. May it remain as it is, and may there be no more whining," an announcement, since deleted, claimed on Kaimiņš' Facebook page.
Later Kaimiņš told Latvian Television his Facebook account had been hacked and the post was not his.
A prior entry on his Facebook entry on Sunday hailed the success of his recently-formed party, Who owns the country? (KPV LV), in several municipalities.
Kaimiņš made his name first as an actor, then as a shock-jock type host of internet talk show Sunu Buda (Dog House) before joining politics.
However his erratic behavior, which includes walking through the corridors of power with a webcam and being arrested after causing trouble in a Riga restaurant, saw him part company with Latvia's Regional Alliance (LRA), the party he was elected to serve.
After a falling-out with LRA leader Martins Bondars, Kaimiņš founded KPV LV.
Later on June 5 Kaimins repeated his claim that his Facebook and other social media accounts had been hacked and that the whole thing was not a stunt, but that he had not asked police to look into the matter. He added that he had no intention of quitting parliament.
But in a bizarre twist, the Kremlin-controlled Sputnik info agency has posted an audio recording of an interview between Kaimiņš and one of its workers, in which Kaimiņš appears to pose as none other than his rival Bondars, offering various views on the municipal election campaign in Riga, where Bondars was a candidate for the mayor's seat (and eventually finished in second place).
In a highly provocative move that could land him in serious trouble, he confirmed that he was Bondars and said a pact had been agreed between LRA and Riga mayor Nils Usakovs - an unfounded and politically sensitive claim.
The reporter had tried to reach Regional Alliance head Mārtiņš Bondars but dialed Kaimiņš' number by mistake, Sputnik admitted.
"I have made the decision that we'll be cooperating with Nils Ušakovs ... We cheated everybody. Our sponsors are the same as those of Nils Ušakovs," Kaimiņš told Sputnik.
The error did at least lead to Sputnik setting a remarkable precedent by apologising to its readers for misleading them - and to Bondars, who may be considering legal action.