Suicide bomber Laachraoui was model student at Brussels Catholic school

Pope Francis holds the book of the gospels as he leads the Chrismal mass in Saint Peter's Basilica at the Vatican March 24, 2016. REUTERS/Stefano Rellandini

BRUSSELS (Reuters) - Brussels suicide bomber Najim Laachraoui was a nice, intelligent boy, his brother said on Thursday, and gave no warning signs of being radicalised before he left for Syria in 2013 and broke all contact with his family.

Laachraoui, a 25-year-old Belgian, was one of Tuesday's suicide bombers, security sources have told local media. A veteran Islamist fighter in Syria, he is also suspected of making explosive belts for last November's Paris attacks.