Paris Olympics organisers have cancelled training for triathletes in the River Seine again because of poor water quality, leading to more uncertainty over whether the mixed relay will go ahead as planned on Monday. All training was cancelled in the river last week and the men's individual race had to be delayed by 24 hours because of pollution problems. It finally took place after the women's event on Wednesday. A heavy rainstorm on Thursday night is believed to have again dirtied the river's waters, with downpours known to cause discharges from the sewers into the waterway.