Protesters angry over police shootings of unarmed black men had vowed to march on Saturday in major cities across the U.S.<br/> <br />They made good on their promise ... with hundreds of thousands of demonstrators reportedly taking to the streets ...<br/> <br />... in Washington, Boston and New York ... as well as smaller protests across the Bay Area and elsewhere.<br/> <br />Organizers say the marches were among the largest in the recent wave of so-called Ferguson protests ...<br/> <br />... venues to vent frustration over the killings of black men by white officers in Ferguson, Missouri, New York and Cleveland.<br/> <br />In Boston, police said they arrested 23 people for disorderly conduct after protesters tried to block a highway.<br/> <br />In New York, demonstrators -- possibly as many as 30,000 of them -- marched along Manhattan's Fifth Avenue.<br/> <br />They sometimes taunted police along the march route and by nightfall they were stopping traffic at the Brooklyn Bridge.<br/> <br />The protests are putting the treat
