After the British general, Louis Bols, read out the Balfour Declaration in February 1920, some 1,500 Palestinians demonstrated in the streets of Jerusalem. A month later, during the 1920 Nebi Musa riots, the protests against British rule and Jewish immigration became violent and Bols banned all demonstrations. In May 1921 however, further anti-Jewish riots broke out in Jaffa and dozens of Arabs and Jews were killed in the confrontations.