Many buildings and streets in the Nepalese capital of Kathmandu are heavily guarded amid an indefinite curfew following two days of deadly anti-graft protests that killed at least 23 people and prompted Prime Minister K.P. Sharma Oli to resign.br br The worst upheaval in decades in the Himalayan nation was unleashed by a social media ban announced last week but rolled back after 19 people died on Sept 8.