Saudi Arabia tightens up hajj planning to avoid repeat of 2015 disaster

Electronic wristbands among measures to keep expected 2 million pilgrims safe from crowd crushes and extremist threat

A year after the worst hajj disaster in a generation, Saudi Arabia is issuing pilgrims with electronic bracelets and using more surveillance cameras to avoid a repeat of the crush that killed hundreds of people and damaged already strained ties with Iran.

The Muslim pilgrimage, which starts on Friday and will bring 2 million people to Islam's most sacred sites in Mecca, will also be a focus of concerns about militant violence after a suicide bomber killed four soldiers in early July in the nearby city of Medina, Islam's second holiest.