Honduran authorities said on Wednesday they had intercepted six Syrian nationals traveling on doctored Greek passports in the past week, including five who had been trying to reach the United States.
Police said there were no signs of any links to last week's deadly attacks in Paris that killed 129 people.
Islamic State claimed responsibility for the shooting and suicide bombing assault.
Five of the men were detained late on Tuesday in the Honduran capital, Tegucigalpa, on arrival from Costa Rica, and had been planning to head to the border with neighboring Guatemala, police said.
They said passports had been doctored to replace the photographs with those of the Syrians.
A sixth man was turned away on Friday on arrival by plane from El Salvador, and was sent back.
They are the first such cases of attempted illegal entry by Syrians into Honduras since the Central American country started compiling records in 2010.