The alleged mastermind of the Paris attacks, Abdelhamid Abaaoud, was reported by French authorities on Thursday to have been killed the previous day during a police siege in the Paris suburb of Saint-Denis. He was born in Belgium to a Moroccan-born immigrant shopkeeper who lives in the Molenbeek-Saint-Jean borough of Brussels and owns a clothing store there. 

As a youngster, Abaaoud attended classes at schools in Molenbeek. Present Mayor Françoise Schepmans says nothing in his conduct led school administrators to believe he might someday became an Islamic radical. Here are some key events in Abaaoud's life:

1999 — At age 12, he is enrolled, apparently briefly, at one of the Belgian capital's most upscale and prestigious secondary schools, Saint-Pierre d'Uccle. One former student says he studied there for two years, while others say the tenure is only half that. Some Saint-Pierre alumni recall a carefree classmate prone to practical jokes, while others remembered him as a rude jerk.

2006-2012 — He is involved in what a Belgian justice official termed "petty crimes," but which appear to have become increasingly serious. Media accounts say his first conviction comes in 2006 for possession of stolen goods, and the second in 2009 for a number of offences including battery with bodily injury. In 2010, he is jailed on suspicion of involvement in a break-in in Ottignies-Louvain-la-Neuve. After his release, his father Omar first notices "signs of radicalization," the shop owner's lawyer says later.

February 2014 — Abaaoud comes to the attention of jihadi analysts as a radical Muslim combatant for the first time. Following a mass execution by the Islamic State extremist group north of Aleppo, Syria, at a place called Hraytan, he is filmed at the wheel of a pickup truck dragging a load of mutilated and beheaded corpses. He uses a nom de guerre, Abou Omar Soussi, wears the same kind of hat as many Afghan mujahedeen, and jokes and appears happy. Sometime in 2014, Abaaoud either entices or brings his younger brother Younes, then 13, to Syria to join him in ISIS-controlled territory. The departure of the boy, dubbed "Syria's youngest jihadi," makes headlines in Belgium, and Abaaoud becomes a household name in his native country.

October 2014 — Abaaoud is last pinpointed in Syria by one independent jihadi tracking group, fighting at this time with a Libyan group named Katiba al Bittar.

Late 2014-early 2015 — He appears to have slipped back into Belgium to help organize and finance an extremist cell in the eastern city of Verviers that reportedly was plotting to storm a police station and kill the officers inside. On Jan. 15, the ring is broken up in a raid that leads to the deaths of two of Abaaoud's suspected accomplices. Abaaoud himself is not there. Belgian Justice Minister Koen Geens said later that "he likely sneaked out again via Greece."

Jan. 17, 2015 — Acting on information from Belgian authorities, Greek police raid an apartment in central Athens and arrest four people, including one matching Abaaoud's description. DNA and fingerprint samples are taken, the man is cleared for extradition to Belgium, but he turns out to be an Algerian national. The following month, Abaaoud is quoted by the ISIS English-language magazine as ridiculing the inability of Western law enforcement to capture him.

July 2015 — Abaaoud is sentenced in absentia by a Belgian court to 20 years' imprisonment for kidnapping his brother and serving as an ISIS recruiter. But according to French officials, Abaaoud's chief focus seems to have shifted back to Europe. French Interior Minister Bernard Cazeneuve said Thursday that he is suspected in four of six attacks thwarted on French territory since spring 2015, including an April plot to attack a church in a Paris suburb and the assault by a heavily armed man inside the Amsterdam-to-Paris express train in August that is foiled when passengers overwhelmed the attacker.

Nov. 13, 2015 — 129 people are killed and hundreds of others are wounded in a series of attacks in Paris.

Nov. 16, 2015 — Abaaoud is identified as ringleader of the three teams of extremists who attacked the French national stadium, Paris cafés and restaurants and the Bataclan concert hall with automatic weapons and suicide bombs. At least one suicide bomber is a Brussels friend of Abaaoud's, as is another suspect still at large.

Nov. 18-19, 2015 — Police storm an apartment building in the Paris suburb of Saint-Denis in a chaotic raid. It takes time for forensic scientists to identify the remains, but a day later, they announce that Abaaoud, along with his cousin, have been killed. It is not yet clear how he died. Cazenueve, the interior minister, also said France didn't know before the Paris attacks that Abaaoud was back in Europe. Officials only were told three days later, on Monday, that he had been spotted in Greece, according to Cazeneuve.

Suspected Paris attacks ringleader confirmed dead3:38