The White House says it is too early to link the Islamic State (IS) militant group to an attack in Texas targeting an exhibit of caricatures of the Prophet Muhammad organized by an anti-Muslim right-wing group.
White House spokesman Josh Earnest said the attack by two gunmen was "still under investigation," adding it's "too early to say at this point" whether IS fighters were responsible.
"This is still under investigation by the FBI and other members of the intelligence community to determine any ties or affiliations that these two individuals may have had with ISIL or other terrorist organizations around the world," Earnest said, using another acronym for Islamic State.
The Islamic State group had earlier in the day claimed responsibility for the attack, saying "two of the soldiers of the caliphate" had carried it out.
Meanwhile, the United States has announced rewards of up to $20 million for information leading to the whereabouts of four top leaders of Islamic State.
The State Department said on May 5 that, through its Rewards for Justice program, it would pay up to $7 million for information on Abd al-Rahman Mustafa al-Qaduli, up to $5 million each for Abu Mohammed al-Adnani and Tarkhan Tayumurazovich Batirashvili, and up to $3 million for Tariq Bin-al-Tahar Bin al Falih al-'Awni al-Harzi.
It said that Qaduli is a senior IS official who originally joined Al-Qaeda's affiliate in Iraq; Adnani is an official IS spokesman; Batirashvili -- known as Umar al-Shishani in the Middle East -- is a battlefield commander in northern Syria who hails from Georgia's Pankisi region; and Harzi is the group's leader for the border region between Syria and Turkey.