The U.S. Embassy in Guyana says it has received "unconfirmed threat information" about a regional airline's flights from that South American country to the United States.
In a warning posted on its website, the embassy urged Americans to avoid using Caribbean Airlines through February 12.
The embassy gave no details on the threat.
A representative for Caribbean Airlines said the company had increased its security "involving the police, the military, and other agencies."
In 2007, a former member of Guyana's parliament and a naturalized U.S. citizen from Guyana were among four people convicted of participating in a failed plot by a small group of militant Muslims to firebomb John F. Kennedy International Airport in New York.
Based on reporting by AP and BBC