In several U.S. cities, at least one healthcare-reform opponent has claimed responsibility for vandalism at Democratic Party and congressional district offices.

The Kansas City (Mo.) Star reported on Tuesday that incidents have been reported in Kansas, Arizona and New York. In one instance, someone threw a brick through the window of the Sedgwick County Democratic Party headquarters in Wichita, Kan., during the weekend.

Vandals destroyed a door and a window Monday at the Tucson office of Rep. Gabrielle Giffords, D-Ariz., who had voted Sunday night in favor of the landmark legislation. Someone threw a brick through a window Friday at the Niagara Falls, N.Y., office of Rep. Louise Slaughter, D-N.Y., a leading proponent of healthcare reform.

The Star also said that a former leader of the Alabama Constitutional Militia Monday claimed responsibility for the attacks.

He issued a call Friday for modern "Sons of Liberty" to break the windows of Democratic Party offices nationwide in opposition to healthcare reform, Mike Vanderboegh of Pinson, Ala., said.

He said in an online posting, "And if we do a proper job, if we break the windows of hundreds, thousands, of Democrat Party headquarters across this country, we might just wake up enough of them to make defending ourselves at the muzzle of a rifle unnecessary."

Leonard Zeskind, author of "Blood and Politics," told the newspaper opponents might "become even more far-fetched and violent," as now that the bill has been signed into law. (With Inputs from Agencies)