Urgent action is needed to tackle a "disturbing" rise in anti-Semitism in Britain including measures to deal with growing "cyber hate" on social media, a group of senior lawmakers said on Monday. Last week, the body which advises Britain's estimated 260,000 Jews on security reported that the number of anti-Semitic incidents in Britain had risen to a record level last year. Many of those incidents were sparked by the 50-day conflict in Gaza that ended in August. Israel launched its Gaza offensive with the declared aim of halting rocket attacks by Hamas. More than 2,100 Palestinians, most of them civilians, were killed, along with 73 mostly Israeli soldiers.The rise in incidents prompted a parliamentary inquiry into anti-Semitism.