UNITED NATIONS, United States — A Philippine diplomat in New York has tested positive for the new coronavirus in the first recorded case at United Nations headquarters in the city, diplomatic sources said on Thursday.

The diplomat, who had last visited the UN on Monday, showed symptoms of flu the following day and saw a doctor.

"She got the call today that she tested positive for COVID-19," said a letter from the Philippines mission.

"As of today, the Philippine mission is in lockdown, and all personnel are instructed to self-quarantine," said the letter obtained by AFP.

The diplomat works at the UN General Assembly's Sixth Committee, which deals with legal matters.

About 3,000 people are employed at the towering riverfront UN headquarters. Numerous other diplomats from the 193 UN member countries come and go between their own missions in the area and the Manhattan UN complex.

The Philippines has confirmed 52 cases of COVID-19 illness. There have been more than 1,600 cases in the United States.