The footage posted on Facebook shows two Southern rail staff, one dressed in an orange high-vis jacket and one in a black uniform, standing over a man who is lying on the ground outside Sutton station in southwest London.
One of the workers can be seen carrying a green bucket over to where the man is lying before sloshing the water inside towards him as people walk past.
The staff member then says something inaudible to the man as he continues to lie on the ground.
A plastic carrier bag, which appears to contain the homeless man’s belongings, can be seen sitting beside him completely drenched.
The man sits up and appears to say something to the worker and his colleague, although his words cannot be made out in the footage.
The person filming the video, who did not want to be named, can be heard telling someone: “I’m filming it because that’s absolutely disgusting behaviour of another human being.”
A male voice, thought to be that of one of the railway workers, can then be heard saying: “Why are you filming it, you don’t need to film it.”
He adds that she should “know the story before you start recording”.
However the woman continues to film, saying: “You still don’t throw water on a man like that.”
One of the workers then begins mopping the ground around the man.
Posting the footage on Facebook on Sunday, the person who filmed the incident said: “This is how Southern fail staff treat another human being in Sutton and I didn’t start filming till they had already whacked him with the mop and put even more water on and around him.
“Complaint raised with Southern fail.”
Angie Doll, passenger services director for Southern Railway, said the two staff members in the video had been suspended while the incident is investigated.
She said in a statement to The Independent: “We take this incident extremely seriously and have started an investigation.
“The two staff members seen in the video have been suspended.
“We would like to apologise to the homeless man and we are trying to make contact with him to offer help and support.”
Sutton Night Watch Homeless Charity said in a Facebook post that the man seen in the video was one of its service users and that he was diabetic.
The charity wrote: “In terribly cold conditions, to have water poured on you and be pushed by a mop is unconscionable, worse still we know this gentleman is diabetic.
“We have contacted the local councillor and an email has been sent to the chief executive of Southern Rail.”
Communities secretary James Brokenshire said: “This shocking act shows a complete lack of empathy towards someone who is vulnerable and in need of help.
“I am writing to Southern Rail to ensure this distressing incident is dealt with swiftly and effectively.”
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