Online death threats have been made against U.N. General Assembly President Miguel d'Escoto Brockmann, and U.S. authorities have been asked to help investigate, an aide said Monday.

Enrique Yeves, d'Escoto's spokesman, said the threats were posted within the past week. He did not say where the threats were posted or elaborate on the nature of the threats.

"Very serious threats have appeared on the Internet against the life of the president of the General Assembly. This matter is being looked into by the pertinent authorities," Yeves said.

D'Escoto, a Roman Catholic priest with openly leftist views, has been critical of the United States and of Israel's treatment of the Palestinians.

He was quoted in The Jerusalem Post in November as saying the international community should consider a boycott, divestment and sanctions against Israel similar to those used against South Africa decades earlier.

The New York Police Department, which provides security around U.N. headquarters in New York, said it had no immediate comment on the reported threats.

D'Escoto, who was born in Los Angeles, served as Nicaragua's foreign minister in the 1980s and is a longtime supporter of Sandinista leader Daniel Ortega.