Tunisia bus blast likely caused by bomber detonating explosive aboard - source

Tunisian police officers are pictured after an attack on a military bus in Tunis, Tunisia November 24, 2015. REUTERS/Zoubeir Souissi

TUNIS (Reuters) - An attack on a Tunisian presidential guard bus that killed at least 11 people was likely caused by a bomber detonating explosives inside the vehicle, a presidential source told Reuters on Tuesday. (Reporting by Tarek Amara; writing by Patrick Markey; editing by John Stonestreet)