Anthony was introduced at a standing-room-only press conference with his wife, the former MTV personality Alani "La La" Vasquez, and the couple's son, Kiyan, now six.

WSJ: Carmelo Anthony's Slam Dunk

As Mr Alani puts it, the network differs from all other militant Islamist movements in its global reach, its focus on very high-value targets and its skill at covering its traces by spiriting agents from one country to another.

ECONOMIST: The al-Qaeda network

The very fact that the eight people detained in Madrid stayed in one country Spain most of the time suggests that they cannot have played a central role in the network, according to Mustafa Alani, an associate of the Royal United Services Institute in London who has been studying al-Qaeda for many years.

ECONOMIST: The al-Qaeda network