Authorities on Friday arrested the Belgian widow of a man involved in killing an anti-Taliban warlord, saying she was part of an al-Qaida group that was about to launch a suicide attack. Malika El Aroud, 49, was charged with belonging to a terrorist organization. Five men in their 20s were also charged; eight others were released for lack of evidence El Aroud, dressed in black from head to toe, was pushed into a police car during a night raid early Thursday a few miles away from, and a few hours before, a summit of European Union government leaders was scheduled to open. Authorities said she was too dangerous to walk the streets and even mulled calling off the summit. "It was considered as a possibility," said Belgian Prime Minister Yves Leterme at summit headquarters. In the end, the summit went smoothly. Authorities still cannot say whether an attack was planned in Brussels or elsewhere. The arrest added to the aura of El Aroud, who is known for using the Internet to support radical causes. "She is a beacon and a catalyzer in the radical movement, and she is very smart in using it," said Brice De Ruyver, a Ghent University professor and former security adviser to Belgian governments. "Our freedom of expression has always given her a safe conduct to use the Internet and attract vulnerable youths," De Ruyver said. One of the five men charged was said to be on the verge of carrying out a suicide attack. Repeated phone calls to the office of her lawyer went unanswered. El Aroud has figured in almost every major Belgian terror probe since 2001, investigators say. An official in the Federal Prosecutor's Office said El Aroud frequently switched laptops and wireless Internet services to evade investigators. The official, who has knowledge of years of investigations into El Aroud, spoke on condition of anonymity because of the sensitivity of the case. Last year, she was detained in a pre-Christmas anti-terrorism sweep, and authorities were convinced at the time that they had averted a terrorist attack. El Aroud has had a tumultuous life. As a child, she moved from her native Tangiers in Morocco to Belgium, where an unhappy youth led to failed relationships before she discovered fundamentalist Islam. She and her husband, Abdessatar Dahmane, went to Afghanistan, where he was killed during the assassination of anti-Taliban warlord Ahmed Shah Massoud two days before the Sept. 11, 2001, terrorist attacks in the United States. Turned into the widow of a martyr, El Aroud returned to Belgium, where, experts say, she has been involved in radical networks in Belgium and Switzerland since. Investigators suspect her current husband, Moez Garsalloui, is now an important link of El Aroud's group in Pakistan and Afghanistan. But Claude Moniquet, the president of the Brussels-based think tank European Strategic Intelligence and Security Center, thinks any attack would probably have targeted someplace in Europe rather than Afghanistan. "Some of the terrorists who were arrested were just back from that country after they had received training; they would not go there anymore," he said. "It is unlikely from a strategic standpoint that a new attack in Afghanistan would change much. In Europe, however, the impact would have been huge."