The United States on Thursday added the Islamic State (ISIS) group’s branches in Libya, Yemen and Saudi Arabia to its global terrorism blacklist and placed six men on its sanctions list, AFP reported.

The three ISIS branches were declared “specially designated global terrorists,” a category that imposes sanctions and penalties on foreign persons who pose a serious risk of committing acts of terrorism that threaten American nationals or national security, the State Department said.

The ISIS group in Libya also was named as a “foreign terrorist organization”, according to AFP.

The designations freeze any U.S. assets the groups may have and make it illegal for any American national to knowingly provide those groups or conspire to provide them with material support or resources.

The State Department said the three groups emerged as ISIS branches in November 2014 when ISIS leader Abu Bakr al-Baghdadi announced he had accepted oaths of allegiance from fighters in Libya, Yemen and Saudi Arabia.

It said that while ISIS’s presence in each country “is limited to specific geographic locations,” the group’s affiliates in all three countries had carried out numerous deadly attacks.

The group’s Yemen branch claimed responsibility for suicide bombings in March 2015 against two mosques in Sanaa, killing more than 120 people.

The ISIS affiliate in Saudi Arabia attacked Shiite mosques both there and in Kuwait, killing more than 50.

In Libya, ISIS has continuously made its presence known and has become a growing threat, as an American official admitted several months ago.

The group’s Libyan affiliate is blamed for kidnapping and executing 21 Egyptian Coptic Christians, as well as killing scores of others.

Last week, American officials said President Barack Obama’s administration is ready to get a UN ban on arms exports to Libya lifted, to help the country’s unity government fight ISIS.

Separately on Thursday, the Treasury Department announced sanctions against six men it accused of providing financial support to terrorist groups.

It said the move was aimed at disrupting the fundraising and support networks of Al-Qaeda, Al-Nusra Front, Al-Qaeda in the Arabian Peninsula (AQAP) and ISIS, according to AFP.

The sanctions target “financiers and facilitators responsible for moving money, weapons and people on behalf of these terrorist organizations,” said Adam Szubin, the Treasury’s acting under secretary for terrorism and financial intelligence.