The Westboro Baptist Church, is blaming same-sex marriage for the shooting dead of two firefighters near Rochester in New York on Christmas Eve.

The church, mostly made up of family members, has already outraged America by blaming this month’s massacre at Sandy Hook elementary school in Connecticut on the state’s equal marriage laws.

The church has repeatedly picketed the funerals of US servicemen and women killed overseas and blames the advances in LGBT rights for everything bad that happens to Americans. 

An online petition for President Obama to classify Westboro as a hate group has attracted more than 270,000 signatures.

Police have said William Spengler, 62, who served 17 years in prison for the 1980 hammer killing of his grandmother, armed himself with a revolver, a shotgun and a semiautomatic rifle before he set his house in Webster, New York, on fire before dawn on Christmas Eve.

The ex-convict who lured two firefighters to their deaths in a blaze of gunfire left a typewritten note saying he wanted to burn down his New York state neighbourhood and “do what I like doing best, killing people.”

On Thursday, Westboro spokesperson, Margie Phelps, tweeted that the firefighters died for “fag marriage” and “other proud sin.”

Shirley Phelps-Roper confirmed the church’s plans to picket the funerals of the two firefighters earlier today. Shirley wrote, “WBC will picket funerals of Lt. Michael Chiapperini &Tomasz Kaczowka,” and included the hashtag “#GodSentTheShooter.”