(Updates with details, quotes)

NEW YORK, March 25 (Reuters) - The office of Representative Anthony Weiner on Thursday received a threatening letter containing an unidentified white powder, his office said.

“Earlier today an envelope containing white powder and a threatening letter was delivered to my community office in Kew Gardens,” the Democratic congressman said in a statement issued by his office.

“My first priority is the safety of my staff and neighbors, and the authorities are currently taking steps to investigate and resolve the situation,” he said.

Weiner’s office in Kew Gardens, part of the New York City borough of Queens, was closed for investigation.

Authorities were responding to the site, and no other details were immediately available, said FBI spokesman Richard Kolko.

The FBI and police are investigating attacks and threats against Democratic members of Congress who voted for healthcare reform, and a senior House of Representatives Democrat said on Wednesday his colleagues are at risk. Weiner voted in favor of the legislation. [ID:nN24147174]

Bricks were tossed through the windows of one member’s office, another lawmaker was spat at by a protester on Capitol Hill and another was the target of a racial slur.

The House gave the healthcare measure -- President Barack Obama’s top domestic priority -- final congressional approval on Sunday. Obama signed it into law on Tuesday.

Emotions ran high among opponents and supporters during the yearlong debate over the legislation. (Reporting by Basil Katz; editing by Ellen Wulfhorst and Xavier Briand)