Human Rights Watch urged the United Nations and member countries on Tuesday to pressure Nicaraguan President Daniel Ortega to halt claimed human rights abuses, including a crackdown on opposition figures ahead of a November presidential election.

In recent weeks, police have detained at least 14 political opponents, including five presidential candidates, drawing international criticism from governments and human rights groups.

In a 38-page report, Human Rights Watch (HRW) said the “high-profile arrests and other serious human rights violations against critics appear to be part of a broader strategy to eliminate political competition, stifle dissent, and pave the way” for a fourth straight Ortega term.

HRW called on the U.N. Secretary-General to raise the issue in the Security Council, saying the growing crisis could undermine stability in the region.

“The Secretary-General once again urges the authorities to uphold international human rights obligations and release the political and social leaders detained. He reiterates his call for a broad-based agreement on measures towards credible, participatory and inclusive elections in November,” the spokesperson said.

Ortega, who is seeking to extend his 14 years in office, returned to power in 2007 having previously led the country from 1979 to 1990.

The “gravity and intensification of the brutal crackdown on the Nicaraguan opposition eliminates any possibility of a free and fair presidential election in November,” HRW underscored.

The Organization of American States’ permanent council this month adopted a resolution to condemn the restrictions and arrests in Nicaragua and called for the release of all political prisoners.