NIAGARA FALLS — The window broken Friday at the Niagara Falls office of Rep. Louise M. Slaughter, D-Fairport, was one of at least four cases of vandalism targeting Democratic offices across the country late last week during the debate over health care reform.

A window was also broken at the Monroe County Democratic headquarters in Rochester.

In Tuscon, Ariz., a window at the office of Rep. Gabrielle Giffords also was broken.

And at Democratic headquarters in Sedgewick County, Kan., a brick with anti-Obama and anti-health care messages was thrown.

At Slaughter’s office on Pine Avenue, a piece of brick and a broken window were discovered at about 12:30 a. m. Friday. The brick shattered the outermost window but not an interior window. Damage was estimated at $350.

Niagara Falls Police Capt. William Thomson, chief of detectives, said officers recovered the brick and found a few scuff marks but were unable to find any fingerprints.

Slaughter spoke of the damage to her Falls office during the debate on the health care bill Sunday on the floor of the House of Representatives.

“The anger isn’t just contained outside the Capitol,” she said. “Last week someone hurled a brick through the window of my district office in the dark of night. We must step back to remind ourselves of why we are here.”

The window remained boarded up Tuesday.

Victoria Dillon, a Slaughter spokeswoman, said Capitol Police are investigating the broken window and a threat left on the voice mail at Slaughter’s campaign office.

Capitol Police did not return calls seeking comment. The FBI also is investigating.

An Alabama-based blog, called “Sipsey Street irregulars,” has launched a “window war” against Democrats and has kept a tally of all the recent window damage, according to CNN.

Blogger Michael B. Vanderboegh told CNN that he called on people to break Democratic Party headquarters windows at the city and county level but not congressional offices because he didn’t want anyone to face federal charges. “I can understand,” he added, “how someone can be frustrated enough to throw a brick through a congresswoman’s window.”