Norway's Karsten Warholm ran a stunning men's 400m hurdles race to obliterate his previous world record and take gold at Tokyo 2020.

Warholm, 25, finished in 45.94 seconds to slash more than seven tenths off his old record, while American Rai Benjamin was hot on his heels to win silver having also beaten the previous record.

Warholm had set the previous world record of 46.70 in Oslo in July.

Brazil's Alison dos Santos took the bronze medal with a time of 46.72.

With the victory, Warholm now holds the European, world and Olympic titles.