The new alert follows another issued a week ago prohibiting US government personnel from using the ferry service between Playa del Carmen and the island of Cozumel.
But it did say that "we do not have information relating the ferry explosion to the security threat in Playa del Carmen". A ferry is pictured in Playa del Carmen, Quintana Roo state, Mexico on February 21, 2018.
The U.S. Consular Agency in Playa del Carmen in the state of in Quintana Roo will be "closed until further notice", the embassy said in a message posted to its official website.
Specific details about the threat were not released, but the embassy advised USA citizens in Playa del Carmen to be aware of their surroundings and to exercise caution.
The State Department issued a "Level 2: Exercise increased caution" alert status for Mexico earlier this year, and now advises US travellers to avoid five states in Mexico: Colima, Guerrero, Michoacan, Sinaloa, and Tamaulipas.
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The judge ordered Manafort to be confined to his home until the trial and wear a Global Positioning System tracking bracelet. Lewandowski helped Trump win the Republican presidential nomination, running his campaign for around 18 months.
Mexican officials also say Playa del Carmen is safe despite the security alert.
Still, Americans were not told to avoid travel to Playa del Carmen. The explosives found on the second ferry were found by a diver cleaning the ship's hull, and the boat had reportedly been out of operation for 10 months.
Canada has issued a new travel advisory for the popular Mexican tourist destination Playa del Carmen.
It was just two weeks ago an explosion rocked the ferry from Playa del Carmen, injuring 25 people, including two Americans.
According to the advisory, Canadians are advised to exercise a high degree of caution when visiting all parts of Mexico "due to high levels of criminal activity, as well as demonstrations, protests and occasional illegal roadblocks".
Last week four gunmen burst into a hospital in Cancun and shot to death a drug gang suspect and his wife. "We do not know the reason for the decision of the USA government to issue this statement", the office said, adding that it is ready to cooperate with the U.S.to ensure the safety of USA tourists.