Although the Nigerian government had reported it defeated the terrorist group Boko Haram, about 110 girls are missing after the militants stormed a school in a small northern town last month.

Here is what should know about the militant group waging a campaign of terror while attempting to establish an Islamic caliphate in Nigeria.

1. Boko Haram is the Hausa language nickname for Jama’atu Ahlis Sunna Lidda’awati wal-Jihad (Congregation of the People of Tradition for Proselytism and Jihad). The nickname, which translates to “Western education is sinful,” was given because of the group’s initial focus on opposing Western education in African countries.

2. Founded in 2002, the terrorist group is comprised of radical Islamists who oppose both Westerners and “apostate” Muslims. Based in Nigeria, Cameroon, and Niger, the organization seeks to establish a “pure” Islamic state ruled by sharia law, putting a stop to what it deems “Westernization.” Its followers are said to be influenced by the Koranic phrase that says “anyone who is not governed by what Allah has revealed is among the transgressors.”

3. Despite the group’s nickname, Boko Haram’s agenda is much broader than just education. The group promotes a version of radical Islam that makes it “haram,” or forbidden, for Muslims to participate in any political or social activity associated with Western society. Prohibitions include voting in elections, wearing shirts and trousers, or receiving a non-Muslim education.

4. In 2009 the group launched military operation to create an Islamic state in Africa. The group carried out a number of attacks on police stations and other government buildings in Maiduguri. Nigeria’s security forces were able to capture the group’s leader, Muhammad Yusuf, the group’s headquarters, and many of its fighters. The Nigerian government thought the threat was suppressed, but the organization regrouped under a new leader, Abubakar Shekau.

5. Boko Haram is currently led by Abubakar Shekau, also known by the nickname Darul Tawheed (“the abode of monotheism”). Shekau took over in 2009 when Muhammad Yusuf died in police custody in Nigeria. He’s described as having a photographic memory, being well versed in Islamic theology, and being extremely ruthless. In a video released after one of the group’s attacks, Shekau said, “I enjoy killing anyone that God commands me to kill—the way I enjoy killing chickens and rams.” Shekau has frequently—and prematurely—been declared dead.

6. In 2015 an audio message, believed to have been by Shekau, was posted on Boko Haram’s Twitter account pledging the group’s allegiance to Islamic State (ISIS). A year later ISIS announced that Abu Musab al-Barnawi was the new leader of the Nigerian group. A few days later, Shekau released a video on YouTube disputing al-Barnawi’s leadership. Since then, Boko Haram has reportedly split into pro-Barnawi and pro-Shekau factions.

7. Since 2009, Boko Haram has carried out numerous attacks against Christians. (In Kano, a city of more than 9 million people, Boko Haram even threatened to kill any Christians living there.) On Easter 2012, a car bombing killed 38 people in the northern Nigerian city of Kaduna. Kaduna lies on the dividing line between Nigeria’s largely Christian south and Muslim north.

8. During the night of April 16, 2014, dozens of armed men from Boko Haram captured over 300 Christian girls aged 12 to 15 who were sleeping in dormitories at Chibok Government Girls Secondary School in northeast Nigeria. Some of the kidnapped girls have been forced into “marriage” with their Boko Haram abductors and sold for a nominal bride price of $12, according to parents who talked with villagers. All of the girls risk being forced into marriages or sold as slaves. The kidnappings were the focus of the “Bring Back Our Girls” social media campaign that garnered significant attention in 2014.

9. Boko Haram has frequently used children—many of them likely kidnapped—as suicide bombers. UNICEF reported four child suicide bombers in 2014, 56 in 2015, 30 in 2016, and at least 83 in 2017.

10. Research by BBC Monitoring shows Boko Haram mounted about 150 attacks in 2017—90 armed assaults and 59 suicide attacks—killing more than 900 people. The attacks occurred in Nigeria, Cameroon, Chad, and Niger. To date, approximately 20,000 people have been killed and at least two million displaced because of the terrorist group.

Joe Carter is an adjunct professor of journalism at Patrick Henry College, an editor for several organizations, and the author of the NIV Lifehacks Bible.

Photo Credit: A screenshot from a July 2014 video released by Boko Haram.