Vandals have targeted the homes of Republican Senate leader Mitch McConnell and Democrat Speaker of the House Nancy Pelosi with graffiti, fake blood and a pig's head, US media said. 

"Were's [sic] my money," and "Mitch kills the poor," was daubed on McConnell's front door and window in Louisville, Kentucky, US media reported.

A pig's head and fake blood were left outside Pelosi's San Francisco home on January 2, according to local media Saturday.

The houses of the top Republican and Democrat were targeted following intense debate over a Covid-19 stimulus bailout for Americans.

A long-awaited $900 billion pandemic relief package was finally approved Christmas Eve, with the Democrat-led House of Congress approving an increase in aid from $600 to $2,000.

But the Republican-led Senate has not approved the increase -- despite furious calls to do so from President Donald Trump.

On Wednesday, McConnell had told reporters: "The Senate is not going to be bullied into rushing out more borrowed money into the hands of Democrats' rich friends who don't need the help."

Kentucky Metro police said the incident occurred around 5am local time Saturday (1000 GMT) according to local news channel WAS11. It was unclear if anyone was home at the time.

McConnell called the graffiti a "radical tantrum," and added: "Vandalism and the politics of fear have no place in our society."

In San Francisco, Pelosi's garage door was sprayed with a crossed-out "$2K", followed by "Cancel rent!" and "We want everything!"

The city's police Special Investigations Division was looking into the incident, NBC News reported.