The Islamic State drew a new round of global condemnation following the release of a video on Sunday purportedly showing the shooting and beheading of 30 Ethiopian Christians in Libya.
However, the authenticity of the video could not be verified, according to Reuters, but the act shown was similar to previous beheadings committed by ISIS militants.
In the video, 15 men were shown being beheaded while 15 other men were shot in the head.
The men were described in the video as "worshippers of the cross belonging to the hostile Ethiopian church."
Ethiopia government spokesperson Redwan Hussein said while the government was not able to verify if those killed were Ethiopians, "Nonetheless, the Ethiopian government condemns the atrocious act."
The White House said "the United States condemns in the strongest terms the brutal mass murder by ISIL-affiliated terrorists of what the murderers claimed are Ethiopian Christians in Libya."
"That these terrorists killed these men solely because of their faith points to the terrorists' vicious, senseless brutality. That's why we continue to support the U.N.-led process to establish a national unity government in Libya as the best hope for Libyans to address this terrorist threat," Press Secretary John Earnest said in a media briefing.
Earnest said "there is continued progress being made in Iraq and in Syria to roll back ISIL fighters from territory that they had previously controlled."
He said there were recent gains in Kirkuk and around the Baiji oil refinery where it was retaken by Iraqi security forces.
"We have long raised concerns about the efforts of ISIL to use social media in a fairly sophisticated way to propagate their hateful rhetoric and to encourage other people to engage in acts of brutality," he said. "And that's something that we continue to be very mindful of, both in terms of our domestic security here in this country, but also as it relates to the spread of ISIS -- or ISIL and their tactics throughout the region."
In the latest video, a man dressed in black with a pistol said, "Muslim blood shed under the hands of your religions is not cheap."
"To the nation of the cross: We are now back again," the man added.
Hundreds of grieving relatives gathered outside the homes of two Ethiopians who were among dozens shown being shot and beheaded by ISIS militants.
So far, only two of the 30 Ethiopian Christian prisoners who were executed by masked jihadists in a video released over the weekend have been identified.
The two were close friends who resided in the impoverished Cherkos district of the capital Addis Ababa.
"My son is gone. I cannot bear it. I am burning," a crying Ahaza Kasaye, mother of Eyasu Yekuno-Amlak, said as family members gathered on Tuesday.
The family was able to identify Eyasu from the video because of his dreadlocks. The bodies of those executed have not been returned or recovered yet.