Norway's double world champion Karsten Warholm made the strongest possible statement ahead of the Tokyo Olympic Games on Thursday by breaking the world record in the men's 400 metre hurdles. Warholm clocked 46.70 seconds in front of an ecstatic home crowd at the 4th Diamond League event of the season in Oslo. The 25 year-old athlete beat 1992 Olympic champion Kevin Young's mark of 46.78 seconds, the longest-standing record in men's track athletics. Brazil's Alison dos Santos was second with a personal best 47.38 and Yasmani Copello of Turkey was third with a season's best of 48.86.