The photos show New Delhi Municipal Corporation employees littering the already clean pavement outside the India Islamic Cultural Centre before Upadhyay, Ilmi and some others cleaned the site with brooms on Wednesday.
As the photographs of garbage being littered for the event found way to Twitter, Congress and AAP came down heavily on BJP, saying the incident "exposed" the sincerity of the government towards cleanliness and that it showed the party's "double standards".
Facing all-round attack, Upadhyay on his part said he was invited by the India Islamic Centre for the event and claimed that he was not aware about garbage being dumped deliberately.
An official of India Islamic Centre said sanitation workers had dumped garbage after realising that there was an event at the site as part of the Swachh Bharat initiative.
Delhi Congress chief Arvinder Singh Lovely, reacting sharply, said BJP has been misguiding people on a number of issues and the incident has "exposed" the party.
"We have been talking about the need for cleanliness in Delhi for last eight years. The BJP-ruled MCD has never taken up the issue seriously. The prime minister has started talking about it only now. It is only photo-op session, not more than that.
"The BJP has been exposed. You can go to any area and will find all the drains are full and overflowing. The BJP-ruled MCDs are not doing anything to ensure cleanliness," Lovely said.
Ridiculing the BJP, AAP leader Ashutosh said the incident reflected lack of seriousness of the much-publicised Swachh Bharat initiative. He also accused the BJP-ruled MCDs of making Delhi a dirty city.
"Is it BJP's cleanliness drive? Narendra Modi's BJP has turned Delhi into a heap of garbage which they have not been able to clean," he said.
When asked, a New Delhi Municipal Corporation official said the sanitation workers who littered the pavement do not belong to the agency though the area falls under it.
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