A bipartisan group of state attorneys general is urging Congress to take steps to further protect state election systems from foreign interference ahead of the November midterm elections.

The 21 attorneys general sent a letter Monday to Sen. Roy Blunt, R-Mo., chairman of the Senate Rules and Administration Committee, and Rep. Michael McCaul, R-Texas, chairman of the House Homeland Security Committee, expressing their “grave concern over the threat to the integrity of the American election system.”