Sri Lankan authorities swept up more people, including foreigners, for questioning on Thursday as they probed deeper into the Easter Sunday bombings, which killed 359 people in potentially the deadliest operation claimed by the militant Islamic State.Police said an Egyptian and several Pakistanis were among those detained overnight, although there was no immediate suggestion that they had direct links to the attacks on three churches and four hotels that also wounded about 500 people.Police on Thursday said 16 more people were detained for questioning overnight, taking the number detained since Sunday to at least 76. That number includes a Syrian national.A police statement said one of those detained overnight was linked to a ‘terrorist organisation’ but gave no other details. It said another was taken into custody after they investigated posts on the individual’s Facebook page and found what they described as ‘hate speech’. “It was related to the spreading and preaching of terrorism,” a police spokesman said.Others have also been caught up in the broader crackdown.Police said they detained an Egyptian who was found not to have a valid visa or passport. The man taught Arabic in a school about 70 km from the capital, Colombo, and had been living in Sri Lanka for more than seven years.A police spokesman also said that a group of Pakistanis had been detained among an unspecified number of foreign nationals for overstaying their visas.The bombings shattered the relative calm that has existed in Buddhist-majority Sri Lanka since a civil war against mostly Hindu, ethnic Tamil separatists ended 10 years ago, and raised fears of a return to sectarian violence. Sri Lanka’s 22 million people include minority Christians, Muslims and Hindus. Until now, Christians had largely managed to avoid the worst of the island’s conflict and communal tensions.Hundreds of Muslims have fled the Negombo region on Sri Lanka’s west coast since scores of worshippers were killed in the bombing of the St Sebastian church there on Sunday. Communal tensions have since flared.Hundreds of Pakistanis fled the port city on Wednesday, crammed into buses organised by community leaders after threats of revenge. “Because of the bomb blasts and explosions that have taken place here, the local Sri Lankan people have attacked our houses,” Adnan Ali, a Pakistani, said as he prepared to board a bus.Sri Lankan officials have said they believed the bombings were carried out in retaliation for the March 15 attacks by a lone gunman on two mosques in New Zealand that killed 50 people.Most of the Easter Sunday victims were Sri Lankans, although authorities have confirmed at least 38 foreigners were also killed. These included British, US, Australian, Turkish, Indian, Chinese, Danish, Dutch and Portuguese nationals.