Three people have been arrested in Morocco on suspicion of involvement in the deadly café bomb last week.
The Interior Ministry described one of the detained men as the main suspect behind the attack, which killed 16 people including British travel writer Peter Moss.
In a statement, they said the man had loyalties to al-Qaida and had tried to travel to terrorism "hotspots" including Chechnya and Iraq.
They said the man had posed as a tourist when he left the bomb near the Argana café in Marrakesh's historic Djema el-Fnaa square and detonated it remotely. They also said he had studied bomb-making online.
Earlier this week the Moroccan ambassador to Britain pledged to "rapidly bring those accountable to justice.