MANAGUA, Nicaragua (AP) — A non-governmental rights group said Thursday that it has confirmed that 63 people died during days of protests over social security changes that convulsed Nicaragua last week, a figure that was not immediately confirmed or denied by the government.

The Permanent Commission on Human Rights added that at least 15 other people are missing and that it had counted over 160 people wounded by gunfire, including nine who lost an eye and two who were left paralyzed.

"What took place is a massacre," said Marcos Carmona, the group's director.

Authorities did not immediately respond to the announcement. The last official death toll provided by the government, 12, came Monday.

Carmona said the organization's count of deaths had increased from 39 the previous evening based on reports coming in from associates across the country.

"We have evaluated them name by name," Carmona said.

Another group, the Nicaraguan Center on Human Rights, said it had received reports from relatives of the dead that they were made to sign letters saying they would not file complaints before being allowed to receive the remains of their loved ones.

President Daniel Ortega's government had implemented a plan to increase the payroll tax and cut pension benefits to shore up Nicaragua's social security system.

That sparked widespread protests, which included many university students, and Ortega canceled the overhaul Sunday. He agreed to talks with different sectors of society.

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