GENEVA, Switzerland — Nearly 23,000 people fleeing turmoil in Nicaragua have sought asylum in neighboring Costa Rica, the UN refugee agency said Tuesday, as it announced a beefed up presence in the region.

Three months of protests against Nicaraguan President Daniel Ortega’s rule and the brutal response by security forces and paramilitary groups have killed more than 300 people, according to rights groups.

“The number of asylum applications by Nicaraguans in neighboring Costa Rica and other countries has increased exponentially,” UNHCR spokesman William Spindler told reporters in Geneva.

Costa Rican authorities have registered nearly 8,000 asylum claims since April and given future appointments to 15,000 other asylum seekers, a delay needed because the processing system is “overwhelmed,” Spindler said.

“UNHCR is strengthening its presence in Costa Rica’s northern border region and… is gearing up its response capacity to provide immediate protection and assistance to thousands of Nicaraguan refugees and asylum seekers,” he added.

While Costa Rica has endured the brunt of the influx, Panama, Mexico and the United States have also seen an increase in Nicaraguan arrivals, UNHCR said.

Ortega, 72, headed a left-wing Sandinista government during the Cold War, and returned to power in 2007.

Protesters have demanded that he and his powerful vice president, wife Rosario Murillo, resign.