A Pakistani-American admitted trying to detonate a bomb in New York's Times Square, US prosecutors said.

Prosecutors charged Faisal Shahzad, 30, a naturalized US citizen born in Pakistan, with five counts, including attempting to use a weapon of mass destruction and trying to kill and maim people within the United States.

"If successful it could have resulted in a lethal terrorist attack, causing death and destruction in the heart of New York City", US Attorney General Eric Holder said of the bomb plot.

Shahzad was arrested late on Monday after he was taken off an Emirates plane that was about to depart for Dubai. Hours later, several of his relatives were arrested in Pakistan, security sources said.

Prosecutors have not said when Shahzad will appear before a judge in Manhattan federal court. He faces a life sentence if he is convicted.

The former financial analyst, who had worked in neighboring Connecticut, was accused of driving a crude homemade bomb of gasoline, propane gas, fireworks and fertilizer into a teeming Times Square on a warm Saturday evening.