The two Boston bombing suspects had intended to come to New York to detonate bombs in Time Square, New York Mayor Michael Bloomberg told a press conference on Thursday.

In a joint press conference with NYC Police Commissioner Raymond Kelly, the mayor said NYC was the suspects' next target.

New York "remains a prime target for those who hate" the US, said the mayor.

Kelly said based on FBI interrogators, the two suspects had planned to drive to New York after carjacking a car in Boston and the remaining explosives were meant for Time Square.

They made the decision to go to NYC in the car, he said, it was a "spontaneous decision".