ENTERPRISE, Trinidad and Tobago — By the time he was 17, Fahyim Sabur had memorized the Quran.

At 23, he was shunning calypso parties and giving private Arabic lessons in his neighborhood here in Enterprise, about 20 miles south of Port of Spain, the capital of Trinidad and Tobago.

A year later, he was on the battlefield in Syria, where he died fighting for the Islamic State.

“He never spoke to me about it,” said his father, Abdus Sabur, 56, who sells meat patties on the street. “National Security called me one day and told me, ‘Your son is dead.’ ”

Law enforcement officials in Trinidad and Tobago, a small Caribbean island nation off the coast of Venezuela, are scrambling to close a pipeline that has sent a steady stream of young Muslims to Syria, where they have taken up arms for the Islamic State, also known as ISIS or ISIL.

American officials worry about having a breeding ground for extremists so close to the United States, fearing that Trinidadian fighters could return from the Middle East and attack American diplomatic and oil installations in Trinidad, or even take a three-and-a-half-hour flight to Miami.