Dias clinched gold in a time of 36.46 seconds in a format in which swimmers across different classifications were graded on points rather than times.

Dias, who swims in the S5 category, beat Italy's S3 competitor Vincenzo Boni into second place after he clocked 47.05 for 1,001 points.

Arnost Petracek of Czech Republic, an S4 swimmer, was third with a time of 42.89 for 988 points. 

Eleven-time Paralympic champion Ihar Boki of Belarus won the men's 200m individual medley elsewhere today.

The SM13 star clocked 2:05.21 for 1,020 points. 

Colombia's Carlos Zarate Serrano accrued 984 points for second place as the SM7 swimmer touched in 2:34.74.

Denrys Dubrov of Ukraine, from the SB9 division, was third in 2:10.11 for 978 points.