SYDNEY, Australia — The authorities in Papua New Guinea confronted asylum seekers on Thursday inside a controversial detention center on Manus Island, ordering hundreds of detainees to leave and destroying their belongings in an attempt to end a standoff at the camp that has drawn international scrutiny to Australia’s offshore detention policy.

By early afternoon, dozens of the asylum seekers had been removed from the camp and placed on three minibuses, said refugee advocates who were at the scene.

“They drove past with their heads out the windows, and they cried, ‘Help us,’” said Tim Costello, chief advocate for World Vision Australia, a charity. “They looked sullen and disturbed and defeated.”

Abdul Aziz Muhamat, a Sudanese asylum seeker in the camp, said the men taken away had been targeted because they were separated from a larger group and were easier to remove. “The problem was, those men split up from the rest of us,” he said.