Manjinder Singh Sirsa and Kapil Mishra, before being stopped and detained by the police, managed to put on one mask on the statue of Gandhi and another on that of a statute at Gyarah Murti sculpture near Mother Teresa Crescent on Saradar Patel Marg.
The legislators were later released by the police.
Manjinder Singh Sirsa, a SAD-BJP MLA, said that it was "shocking" that the Kejriwal government collected Rs 787 crore of environment cess but spent only Rs 93 lakh out of it.
Kapil Mishra is a suspended MLA of Aam Aadmi Party.
The Gyarah Murti sculpture including eleven statues depicts Dandi March of 1931, with Mahatma Gandhi leading men and women including some prominent leaders of the national freedom movement.
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