Ellie Simmonds of ParalympicsGB has won gold in the S6 400m freestyle, setting a new world record in the process.
The world record was broken by almost five seconds, with Simmonds setting the new one at 5:19.17.
Arlen had to settle for silver in a time that would have broken the initial record, 5:20.18.
Song Lingling came third to take bronze with 5:33.73 but there were only ever two in the race for gold.
Natalie Jones also made the final, but she could only manage seventh.