Swimmer Nyree Kindred won Great Britain's first medal in the pool when she was second in the S6 100 metres backstroke with a world record from China's Lu Dong needed to beat the Briton at the Aquatics Centre.
The 32-year-old won this event in Athens in 2004 before being edged out by Holland's Mirjam De Koning-Peper four years later.
Lu led from start to finish after a superb kick off the wall with Kindred some way back before moving through the field to turn in third but the Briton was coming back with each stroke of the second length before the Chinese swimmer held on to touch in one minute 24.71 seconds with Kindred second in 1min 26.23secs, just 0.04secs outside the old world record.
Kindred's race was the second of the session with Zheng Tao having claimed the first gold in the pool of London 2012 when he won the S6 100m backstroke in a new world record of 1min 13.56secs.
Kindred told Channel 4: "The crowd lifted me. They were brilliant. I'm glad they're all here.