Muslim pilgrims have been streaming into Saudi Arabia's holy city of Mecca for the Hajj, as the annual pilgrimage returns to its monumental scale. Saudi officials say more than 1.5 million foreign pilgrims have arrived in Mecca so far. More are expected, and hundreds of thousands of Saudis and others living in Saudi Arabia will also join them when the pilgrimage officially begins on Friday. (AP video by Bassam Hatoum, Baraa Anwar and Rafiq Maqbool).