In the United States, at least 25 people have been injured in an explosion in New York City. Officials say fire trucks and ambulances converged on the scene after what witnesses described as a deafening blast in the Chelsea district of Manhattan today. A local official told US media FBI and Homeland Security officials are at the scene. The cause of the explosion is unclear. <br/><br/>The New York Fire Department said none of the injuries appear to be life threatening. <br/><br/>The explosion comes just hours after a pipe bomb exploded in a New Jersey town, shortly before thousands of runners were to participate in a charity race nearby. No injuries were reported in the New Jersey blast.