Egypt striker Salah was filmed on a mobile phone as he took a corner.
The footage, shot with a fan, shows expletives aimed at Salah including about his Muslim religion.
In a statement, West Ham said that they have”a zero tolerance policy to some form of violent or violent behavior”.
It continued:”We’re an inclusive football team.
“Regardless of race, religion or belief, union or civil partnership, pregnancy or childbirth, sex, sexual orientation, sex reassignment or disability, everybody is warmly welcomed in London Stadium.
“anybody identified committing an offence will have their details passed into law enforcement and will face a lifetime ban from London Stadium.
“There isn’t any place for this sort of behavior at our stadium.”
The consumer that posted the video on Twitter said:”I had been mesmerized by what I had been hearing. People such as this deserve anywhere within our society aside from football matches”
Police are aware of the incident.