An Indian national allegedly plotted to assassinate an Indian-American attorney and political activist in New York City, authorities said Wednesday.

Nikhil Gupta, 52, allegedly a drugs and arms trafficker, was allegedly recruited in May by an Indian government employee to assassinate the Indian-American activist, per a statement from the U.S. Attorney’s Office for the Southern District of New York. The activist is a vocal critic of the Indian government and leads a U.S.-based organization banned in India that advocates the secession of the Sikh-dominated northern Indian state of Punjab, the statement noted.

Gupta, in collaboration with the Indian government employee, hired a hitman to commit the assassination for the sum of $100,000 and paid the hitman $15,000 in advance in June, not knowing that the hitman was a Drug Enforcement Administration (DEA) undercover officer, the statement alleged.

Both suspects allegedly extensively surveilled the activist. Gupta previously allegedly warned the hitman against committing the assassination around an anticipated meeting between high-level U.S. and Indian government officials.

Following the assassination of the Sikh activist Hardeep Singh Nijjar outside a Sikh temple in British Columbia, Canada on June 18,  Gupta allegedly told the hitman that Nijjar “was also the target” and “we have so many targets,” the statement noted.  The Indian government employee notified Gupta on June 20 that “[i]t’s [a] priority now,” per the statement.

Gupta faces up to 10 years in prison if convicted of murder-for-hire and another 10 years if convicted of conspiracy to commit murder-for-hire, the statement noted. (RELATED: Canada Accuses Indian Government Of Assassinating Religious Leader On Its Soil)

The targeted activist was identified as Gurpatwant Singh Pannun, CBC News reported.

“I am grateful that my Office and our law enforcement partners neutralized this deadly and outrageous threat,” U.S. Attorney Damian Williams said, per the statement. “We will not tolerate efforts to assassinate U.S. citizens on U.S. soil, and stand ready to investigate, thwart, and prosecute anyone who seeks to harm and silence Americans here or abroad.”

Meanwhile, Canada and India have been embroiled in a diplomatic spat following Canadian Prime Minister  Justin Trudeau’s statement that the Indian government was involved in Nijjar’s assassination.