As Modi arrived for his first address to the UN General Assembly, a large number of Indian-Americans gathered outside the UN headquarters to welcome him.
The crowd, comprising almost equal number of men and women, carried placards with messages like 'New York loves Modi', 'America loves Modi' and chanted 'Modi Modi' slogans.
But soon representatives of some Kashmiri separatist groups shouting anti-India slogans arrived at the scene carrying banners.
Protesters belonging to seven groups, including All Jammu and Kashmir Muslim Conference, Jammu Kashmir Liberation Front and All Parties Hurriyat Conference, handed out flyers to the media of a letter addressed to UN Secretary-General Ban Ki-moon.
"The people of Kashmiri origin settled in the US have come to your door today to voice their outrage over the honour extended by the UN to Narendra Modi," the letter said.
The groups also lambasted Modi for the 2002 Gujarat riots and even raised the issue of cancellation of Foreign Secretary-level talks between India and Pakistan.
India and Pakistan have been involved in a war of words after New Delhi cancelled the Foreign Secretary-level meeting last month after Pakistan's envoy in India met Kashmiri separatists ahead of the talks.
"Modi abruptly called off the peace talks with Pakistan throwing the region into turmoil," the letter by the groups said.
The groups sought the intervention of Ban to end the current stalemate in the sub-continent.
"You have the responsibility to secure for the Kashmiri people their inalienable right to self-determination as mandated by the Security Council resolution," the letter said.
What started as a support rally for Modi soon turned into a war of words between his supporters and representatives of some Kashmiri separatist groups as they shouted slogans against each other.
The representatives of the Kashmiri separatist groups shouted anti-India slogans.
Police barricaded the two groups and stood between them to avoid a clash. Both the groups were standing opposite to each other.
The representatives of the Kashmiri separatist groups, included women and children. They carried placards that read: "Justice for Kashmiris" and "We want freedom of Kashmir."
Heavy police deployment and barricading was seen at the UN Building.
Image: Protesters belonging to Kashmir-based groups display placards and shout slogans during a protest outside the United Nations Headquarters where Prime Minister Narendra Modi was attending the 69th UN General Assembly session in New York. Photograph: PTI Photo