BRUSSELS, April 9 (Reuters) - Belgium's public prosecutor charged four men on Saturday with terrorist activity for their suspected roles in last month's Brussels bombings that killed 32 people and November's Paris attacks that claimed 130 lives.
The four were arrested on Friday, along with two others who were later released. Belgian police raided a suspected safe house in central Brussels on Saturday but found no weapons or explosives and made no further arrests.
Belgium's federal prosecutor said Mohamed Abrini admitted to being the "man in the hat" seen accompanying two suicide bombers at Brussels airport on March 22.
"We confronted him with the video evidence prepared by our special unit," a spokesman for the prosecutors' office said. "He had to admit it was him."
Abrini had been on Europe's most wanted list since December, after he was caught by a security camera at a motorway service station with suspected militant Salah Abdeslam while they drove to Paris two days before the attacks there.
"He is charged with participation in the activities of a terrorist group and terrorist murder," the Belgian federal prosecutors office said in a statement.
Prosecutors said they also charged Osama K, who local media said was a Swede named Osama Krayem, adding they were able to identify him as the man present at the time of the attack on the Brussels metro station that same day.
Osama K was seen buying the bags used in the Brussels attacks in a shopping center there, prosecutors said.
The other two were Bilal El Makhoukhi, who had already been convicted for working with jihadist recruiters, and a Rwandan named Herve B.M. on charges of helping Abrini and Osama K.
The arrests were a sign of success for Belgian security services, which have been criticized at home and abroad since Brussels-based militants organized the attacks in Paris and, four months later, those in the Belgian capital.
Belgian Prime Minister Charles Michel said his government would continue to be vigilant about the militant threat.
"We are positive about the recent developments in the investigation. But we know we have to stay alert and cautious," Michel told a news conference in Brussels.
El Makhoukhi was convicted in January last year for being involved in Sharia4Belgium, a now disbanded organization that recruited people to go fight alongside jihadist organizations in Syria and Iraq, Belgium's Justice Minister Koen Geens said.
Originally sentenced to five years in prison, with three years suspended, he was allowed to serve his remaining term at home under electronic monitoring and was released last month, Geens told reporters.
"He was under electronic supervision and his sentence ended on March 15," Geens said at a government news conference.
El Makhoukhi was convicted last year following his return to Belgium after losing a leg while fighting in Syria.
Prosecutors said they had charged El Makhouki, whom they named as 27-year-old Bilal E.M., with participation in the activities of a terrorist group and terrorist murders.
"He is suspected of having offered assistance to Mohamed Abrini as well as Osama K," prosecutors said.