The 158th University Boat race between Oxford and Cambridge had to be halted after a protester jumped into the river Thames and swam towards the boats. The umpire stopped the race after seeing the man almost collide with the Oxford boat's oars. He was first spotted by Olympic medallist Sir Matthew Pinsent who was acting as assistant umpire.
The swimmer was later identified on Twitter as an activist called Trenton Oldfield. He had posted a blog beforehand announcing his plans and saying it was a protest against elitism.
Police arrested him on suspicion of a public order offence and he was held in custody at a west London police station. The race was restarted but there was soon another controversial incident. The two boats got too close and one of the Oxford oars broke as they collided. With only seven men to row, the Oxford boat was at a disadvantage and Cambridge raced away to victory.
But the race had a worrying ending - one of the Oxford crew, Dr Alexander Woods, collapsed in the boat and had to be taken to Charing Cross Hospital. A medical report said he was in a stable condition.