Amritpal Singh, who has revived calls for the state of Punjab to secede, had been on the run since last month after capturing national attention in February. Indian police on Sunday arrested a separatist leader who has revived calls for an independent Sikh homeland and the secession of India’s northern Punjab state, which has a history of violent insurgency. Amritpal Singh had been on the run since last month after capturing national attention in February, when hundreds of his supporters stormed a police station in Ajnala, a town in Punjab state, with wooden batons, swords and guns to demand the...