Washington (CNN) U.S. intelligence estimates now put the number of ISIS fighters in Libya between 4,000 to 6,000, double the number in the war-ravaged country last year, according to the top U.S. military commander in Africa. Gen. David Rodriguez, commander of U.S. Africa Command, said the intelligence community estimates the number of ISIS fighters in Libya at "around 4 to 6,000." He added that the number has "probably about doubled in the last 12 to 18 months, based on what their assessments were last year." Wracked by violence since the fall of Moammar Gadhafi in 2011, Libya has become a haven for militant groups.Libya has become a haven for militant groupsMany of the foreign fighters flooding into Libya come from other northern African countries
The U.S. continues to watch _ closely, Rodriguez told reporters Thursday.