Tap above to watch video report by Chloe Keedy
A bus carrying Jewish teenagers through central London was spat at by a gang of men who hurled anti-Semitic slogans.
Disturbing video posted online shows the bus being attacked on Oxford Street as the teens celebrated Hanukkah.
Rabbi Shneor Glitsenstein of the Chabad Israeli Centre Golders Green told the Jewish Chronicle the men starting shouting "Free Palestine".
He said the bus was targeted while it waited in traffic close to the Primark store. As it drove away one man started banging on the window.
Speaking to ITV News London Dave Rich from the Community Security Trust said: "They hired a bus to go down Oxford Street, they were dancing, singing and handing out food to people.
"All of a sudden a group of men who saw them passing by started shouting anti-Semitic abuse, making threatening and violently aggressive gestures towards them," he added.
London Mayor Sadiq Khan said antisemitism had "no place whatsoever in society", adding: "I utterly condemn these disgusting acts. No one should have to experience this. "If you have any information about this incident, I urge you to report it," Mr Khan said.
Police said they were aware of the video which was filmed on Monday evening.
A police statement said: "The occupants of the bus were Jewish and the abuse directed at them was allegedly antisemitic in nature. While they were en route, the bus left the location to avoid any further confrontation.
Officers met it in Grosvenor Place to speak to the occupants and check on their welfare. Details of the incident were taken. There were no reports of any injuries," the statement added.
Officers are treating the case as a hate crime and are still looking for the men seen in the video. There have been no arrests.
Anyone who recognises the men or has other information that may help officers, can call police on 101 with the reference 6187/29NOV. Information can also be provided to Crimestoppers, anonymously, on 0800 555 111.