LONDON — The police force in Britain’s capital has been forced to issue two apologies after officers threatened to arrest an “openly Jewish” man if he refused to leave the area around a pro-Palestinian march because his presence risked provoking the demonstrators.

Gideon Falter, chief executive of the Campaign Against Antisemitism, was wearing a traditional Jewish skullcap when he was stopped by police while trying to cross a street in central London as demonstrators filed past on April 13.