The theft is understood to have taken place at 1:15pm in Deptford, south-east London. Groups of around 20 residents believed to be from the area were allegedly involved.
Hugh Brasher, Event Director for London Marathon Events Ltd, said: ‘It’s very disappointing to see water being stolen in this way from the official water stations for our runners.
‘These water stations are staffed by volunteers and we are very grateful to them for their work on Race Day.
‘We always brief our volunteers not to get into altercations if this kind of thing happens. We’ll investigate this further.’
A Deptford man caught the whole incident on camera.
He said: ‘Just after the first lot of runners went through all the residents around the Deptford area just started looting and stealing all the water from the runners.
‘I just find that absolutely disgusting, absolutely appalling. I wouldn’t know why they would do that.
‘Why would you go crazy – like animals – and steal all the water? I think it’s absolutely vile behaviour. They were young and old.
‘There were parents there with their buggies shoving it and putting them wherever they could.
‘There was one guy in the picture who had a trolley just ready to take them. They then started darting off in different directions.’
The footage provoked angry reaction on social media. One user posted: ‘That video of people in Deptford pinching all the water for the #LondonMarathon is absolutely vile! They should be ashamed of themselves!!’
Another commented: ‘Wow, that video of the locals in Deptford stealing bottled water meant to be for the marathon runners. Animals.’
A third said: ‘Why steal the marathon runners’ water. How about chill out at home and just open your cold tap?’ A London Marathon source said the bottles were taken towards the end of the race, when only the runners at the back were passing though and no participants were deprived of water because of the incident.
However, any spare water which was not drunk during the marathon was supposed to have been returned to organisers to use at other events.
Therefore, non-runners helping themselves to water were doing so without permission.