"In our country it doesn't take much for allegations to come up against politicians...This person made 50 crores, that son made 250 cr, that daughter made 500 crores, someone's damaad (son-in-law) made 1000 crores..." PM Modi said at the packed SAP Centre.
The pause after "damaad" was filled with titters from the gathering. (Live updates of PM Modi's US visit)
This is not the first time the prime minister has used the term, which is seen to reference Congress president Sonia Gandhi's son-in-law Robert Vadra and his controversial land deals.
PM Modi questioned the 18,000-strong audience: "Aren't you sick of all of this? Aren't you angry? My countrymen, I am standing in your midst. Is there any allegation against me?" He got a resounding "No".
"I'm only going to live for the country and die for the country," declared the 65-year-old prime minister.
The Congress reacted sharply, saying it was unbecoming of the prime minister to criticize the opposition on foreign shores.
"It is in poor taste and condemnable. The Prime Minister indulges in defaming members of a family that has immense contribution in building this country," said senior Congress leader Anand Sharma, accusing Mr Modi of dragging the political narrative of India to a "gutter level."
"It is disturbing to see that this great country has been represented by a showman. This country didn't take birth on May 16 last year (when Mr Modi took power)," Mr Sharma said.
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