Hezbollah, Hamas and Al-Qaeda, have a strong presence in South America. They are particularly active in the Tri-Border Area (TBA), the region where Brazil, Paraguay and Argentina meet.
Ten Brazilians who pledged allegiance to the Islamic State militant group were arrested Thursday, accused of planning attacks during next month's Olympics.
Brazil is revising its security for next month's Summer Olympic Games in the wake of the attack in Nice, France, that killed 84 people.
The DEA alleges that some Hezbollah members used millions of dollars gained through cocaine sales in the US and Europe to fund operations in Syria and Lebanon.
Health officials have confirmed that two people contracted the Zika virus via a blood transfusion - days after a sexual transmission of the disease was reported.
CDC: Doctors should ask pregnant women about their travel and certain symptoms, and – if warranted – test them for the Zika virus.
The Arkansas Department of Health says a person who recently traveled out of the United States has tested positive for the Zika virus.