US president Donald Trump's criticism of American football players who kneel during the national anthem has sparked a mass increase in such protests around the NFL, as about 200 players sat, knelt or raised their fists in defiance.

With control of Congress at stake in tomorrow’s elections, US president George Bush campaigned in endangered Republican districts across conservative states while the top congressional Democrat campaigned for her party in the left-leaning North-East.

The death toll from the Washington sniper rose to seven as ballistics evidence linked the killer to a man gunned down at a Virginia petrol station.