Jamaica's Elaine Thompson has secured her second sprint gold medal of the Rio Olympics by winning the women's 200m final here.The 24-year-old crossed the line in a season's best 21.78 seconds, a tenth of a second ahead of world champion Dafne Schippers of the Netherlands on Wednesday, reports Xinhua news agency.Tori Bowie of the US claimed bronze in 22.15.Thompson, the 200m silver medallist at last year's World championships, clinched the Olympic 100m title on Saturday with Bowie taking silver.