The leader of Boko Haram, Abubakar Shekau, pledges allegiance to the ISIS group in a new audio recording posted on the group's Twitter page, according to the BBC and the SITE Intelligence Group, which monitors jihadist propaganda. VICE could not independently verify the recording.
The message is just the latest evidence of how the Nigerian militant group has apparently been influenced by the Islamic State.
Last week the group released a video allegedly showing the beheadings of two men in the style similar to the dramatically produced videos of executions by the Islamic State's media wing.
The 6-minute video of the executions was a very different kind of video than from previous Boko Haram video releases, which often showed Shekau speaking directly to the camera and going on long tangents about the militant group.
Before the pledge to ISIS, the militant group also appears to have been inspired by the Islamic State to create their own "caliphate" in northern Nigeria.
The alleged pledge of allegiance from Shekau comes after reports that Nigerian and other government forces have continued to launch offensives against Boko Haram strongholds, according to the Associated Press.
Militants are preparing to face-off with multinational government troops, according to an AP report. Citizens who fled the area under Boko Haram's control reported seeing members of the group readying for a showdown.
Shekau's reported message also comes hours after five bomb blasts ripped through the Nigerian city of Maiduguri, killing 54 people, according to the AP. Boko Haram has not taken responsibility for the bombings, but the bombings appear similar to past attacks by the militant group. The city of Maiduguri is the birthplace of the Boko Haram and has been hit by multiple terrorist attacks since the group launched in 2009.
In recent years violence has intensified in the area around northern Nigeria, as Boko Haram killed at least 10,000 people in Nigeria, Cameroon, Chad and Niger. Boko Haram has made headlines for massive kidnappings of students along with multiple bombings in Nigerian cities including the capital of Abuja. Since the insurgency started in 2009, the violence has displaced approximately 1.6 million people in the region.
Chad's President Idris Deby announced earlier this week that he knew the location of Shekau, according to the AP, and said if the leader did not turn himself in, he would be killed.
Follow Gillian Mohney on Twitter: @gillianmohney