U.S. President Barack Obama has issued a statement connected to the attack inside the Canadian Parliament Building.

CRI's Washington chief correspondent Xiaohong with more.

Obama is describing the shooting in and near the Canadian Parliament Building as 'tragic".

"It emphasis the degree to which we have to remain vigilant when it comes to deal with this kind of accidents, sense of violence or terrorists."He says he's spoken on the phone with Canadian Prime Minister Stephen Harper, and has offered U.S. Assistance.

奥巴马回应渥太华枪击案"When it comes to deal with terrorist activities, Canada and the United States has entirely to be in sync. We had in the past, and I'm confident we'll continue to do so in the future. "Meanwhile, the Canada-U.S. North American Aerospace Defense Command says it has taken steps to potentially respond to any incidents involving aviation.

Security has also been also tightened at the Tomb of the Unknown Soldier at Arlington National Cemetery just outside Washington.

The New York Police Department has also put on extra security at the Canadian consulate in Manhattan.

Xiaohong, CRI, Washington DC.