A group of scientists studying the San Fermín festival in Pamplona, Spain, believe there’s a way to predict the motions of a large crowd.

The Maha Kumbh Mela, a Hindu festival in India that is drawing hundreds of millions of pilgrims, is a powerful marketing tool for Prime Minister Narendra Modi and his allies.

The late release of casualty figures at the gathering of millions of people was seen as shielding the political fortunes of a local leader with national aspirations.