Washington is mulling over the option of fresh military action against the Islamic State group — also known as ISIS — in Libya, four years after it conducted an air campaign that toppled the country’s long-time dictator Moammar Gadhafi, Peter Cook, a spokesman for the U.S. Department of Defense told reporters Wednesday. U.S. warplanes had ceased their operations in Libya four years ago after Gadhafi’s body was dragged through the streets of Tripoli, raising questions over the need of a U.S. intervention in Libya.

Cook said the U.S. had to revisit the question of going to war in Libya because of the “metastasis” of ISIS from its base in Iraq and Syria, the Guardian reported. The question over U.S. presence in Libya had become more crucial after four Americans, including a U.S. ambassador, were killed during a terrorist attack in the city Benghazi in 2012. Senator Ted Cruz, a leading Republican leader, has said that waging war in Libya made “no sense.” The issue of an armed intervention in Libya has also become a matter of contention for the Obama administration, as Hillary Clinton, who was Secretary of State at the time of the Benghazi attack, is running for president.

Cook said, according to the Guardian, that Washington was “looking at military options” in Libya and a “small group” of U.S. forces had got in touch with militiamen in Libya to “get a sense of who the players are.” He also reportedly said: “We are extremely worried about the metastasis of ISIL (another name for ISIS) in a number of locations, Libya being just one of those locations.”

Cook did not clarify the number of U.S. forces that participated in the mission or if they were still operating in Libya. The Guardian report went on to estimate that the U.S. personnel may be a part of special operations forces. Cook added that the move of trying to know more about conditions in the North African country was just a broad assessment instead of “shaping operations”, which are done before an impending attack.

“They’re trying to get a clearer picture of what’s happening there, and they’ve made contact with people on the ground to try and get a better sense not only of the threat that [ISIS] poses there but the dynamic on the ground in terms of the security situation,” Cook said, according to the Guardian, adding: “We’re looking for partners who can give us a better sense of the security situation, and it’s not just the United States that has a keen interest here, it is our foreign partners as well.”

According to a report by the New York Times, there are about 3,000 ISIS fighters in Libya and Gen. Joseph Dunford Jr., the chairman of the Joint Chiefs of Staff, said last Friday that military officials were planning to “take decisive military action” against ISIS.

A report by Soufan, a New York City-based security group led by former FBI agent and 9/11 investigator Ali Soufan, said Wednesday that ISIS and the al Qaeda group were rapidly expanding in Libya, which currently has an unstable political framework.

“Given geography, expansive territory, extensive oil reserves and its history with violent jihadist networks, a failed state in Libya could be disastrous for North Africa and Europe as well as the broader international community,” the group said in the report.

The report also said the fight for Libya’s large oil reserves made matters worse and “allowed violent extremist groups such as the Islamic State and al Qaeda to thrive.” The report added that even if democratic elections led to the formation of a unity government, the leader would face “the monumental task of reuniting the country both socially and militarily.”

A report by Russia Today said, citing Human Rights Watch, that about 400,000 people have been displaced from Libya due to the ongoing civil war that started after Gadhafi’s death. Soufan also said in its report, according to Russia today, that ISIS and al Qaeda are “utilizing Libya as a safe haven from which to launch operations against neighboring countries.”

U.S. warplanes are already operating in Libya, according to Russia Today. In December last year, the U.S. admitted to carrying out an air raid in the country in November that killed suspected ISIS leader known as Abu Nabil.