London 2012: Adlington leads Team GB's medal hopes

Great Britain's medal hopes on day two of London 2012 include swimmer Rebecca Adlington, who will be hoping to retain her 400m freestyle title.

The first day of Olympic sailing begins at Weymouth Bay, where Briton Ben Ainslie will begin his quest for a fourth Olympic gold medal.

Gold medal-winning cyclist Nicole Cooke will compete in the woman's roadrace.

Meanwhile, Locog is investigating why hundreds of seats were empty at events including swimming on Saturday.

Mansfield-born Adlington won two gold medals in Beijing and will be defending her 800m freestyle title as well as her 400m title in heats at the Aquatics Centre later.

Andy Murray - who was defeated with his brother Jamie in the tennis doubles on Saturday - will play Stanislas Wawrinka in the singles at Wimbledon

As well as the individual events, British teams will also compete in basketball, handball, hockey, volleyball, water polo and the football on Sunday.

The BBC's Nick Hope said areas high in the stands or the swimming session at the Aquatic Centre, in east London, on Saturday morning were full, but that several hundred more expensive seats closer to the pool were empty.

Empty seats were also seen at Wimbledon, the volleyball at Earl's Court and the gymnastics at the O2.

Locog said most of the empty seats were believed to have been for accredited groups such as media and governing bodies.

"Many of our venues were packed to the rafters today. Where there are empty seats, we will look at who should have been sitting in the seats, and why they did not attend," a spokesman said.

BBC correspondent Andy Swiss says ticketing is a sensitive issue after many fans missed out and the empty seats are a problem Locog will be anxious to solve.

In other Olympic developments: