A 22-year-old Moroccan man has been arrested in Italy under suspicion of being involved in the deadly March 18th shooting at the National Bardo Museum in Tunis, according to NBC News (see Gunmen Kill 24 Including Tourists in Attack at Tunisia’s National Bardo Museum).

On Wednesday, Touil Abdel Majeed was arrested outside of Milan by the country’s anti-terrorism force, DIGOS (Divisioni Investigazioni Generali e Operazioni Speciali). Italian police say Majeed arrived in Italy by migrant boat, and was given a deportation warrant, NBC News reports.

Tunisian authorities arrested nine suspects following the attack (see Nine Arrests as ISIS Claims Credit for Bardo Museum Attack in Tunisia). To date, nearly two dozen suspects have been taken into custody. Although ISIS publicly claimed credit for the shooting, Al Jazeera reports that the police suspect the Okba Ibn Nafaa Brigade, which is the North African arm of al-Qaeda.

On March 28, a police raid on along the Tunisia-Algeria border killed nine members of the group, including Khaled Chaieb, also known as Lokman Abou Sakhr, the suspected Bardo Museum mastermind, according to Reuters. A day later, thousands marched in the streets of Tunis, declaiming violence. “I tell the Tunisian people: ‘Forwards. You are not alone,'” President Beji Caid Essebsi told the crowd, Al Jazeera reports.

The museum’s reopening was delayed as a result of the shooting. Instead of opening on Tuesday, March 24th, the institution held a symbolic ceremony that day, according to BBC News. It officially reopened on Sunday, March 29th (see Security Threats Force Bardo Museum to Postpone Reopening).