(CNN) Days before the Carnival on the islands of Trinidad and Tobago, multiple US officials tell CNN they are aware of a terror-related threat to the popular annual event.

This year's Carnival will be held Monday and Tuesday.

The US Embassy in Port of Spain, capital of the two-island Caribbean nation, issued a security alert Thursday night, saying a plot had been thwarted but advising US government personnel "to exercise additional caution and increased situational awareness if they participate in Carnival events."

The United Kingdom also issued a "Foreign Travel Advice" for the West Indies country on Thursday.

"Terrorists are very likely to try to carry out attacks in Trinidad and Tobago. Attacks could be indiscriminate, including in crowded spaces and places visited by foreigners," the advisory said, adding authorities in that country have made arrests.

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