Three people are confirmed dead and many others injured after a shooting at a private school in the US state of Wisconsin, including a child who caused the attack, authorities said.

Madison Police Chief Shon Barnes was speaking to reporters on Monday when the death toll rose. He offered no details on the victims but says others were wounded in the shooting at Abundant Life Christian School.

Barnes says police officers who responded did not fire their weapons.

Police had blocked off roads around the school on Monday afternoon.

President Biden has been briefed on the shooting in Madison, according to the White House, which said senior administration officials were in touch with authorities to provide support as needed.