In a stinging editorial in the party mouthpiece 'Dopahar Ka Saamana', Thackeray said Kejriwal had issued "a certificate of honesty" to Delhi BJP chief Harsh Vardhan, now the opposition leader.
"During the debate on the vote of confidence, Vardhan exposed the veil of honesty of Kejriwal and Co and explained in detail how the AAP chief and his supporters are fooling the people," Thackeray said.
Accusing the AAP of playing with the sentiments of the people, Thackeray said Kejriwal had termed as "fake" the Batla House gun battle in Delhi in which three terrorists were gunned down and a policeman was martyred.
"He has also insulted our brave soldiers fighting enemies on the country's borders... This statement (by Kejriwal) is nothing short of treason for which Kejriwal must apologize," Thackeray said.
"Kejriwal and Co had spoken about travelling to work by metro rail and not occupying big government bungalows. But ... they threw to winds all their promises and assurances," he said.