Then the Roman army began its march north, following the coastal road. 300 horse under John the Armenian were detached as an advance guard some 3 miles (4.5 km) in front of the main army, while the 600 Huns covered the army's left flank. Belisarius himself with his "bucellarii" led up the rear, to guard against any attack from Gelimer, who was known to be in the vicinity. The fleet followed the army, sailing along the coast. The first town they encountered was Syllectum, which was captured by a detachment under Boriades by a ruse. In an attempt to sow division among the Vandals, Belisarius gave a letter written by Justinian and addressed to the Vandal nobles to a captured Vandal messenger, in which the emperor claimed to be campaigning on behalf of the legitimate king Hilderic against the usurper Gelimer. As the messenger was too afraid to deliver the letter, this ploy came to nothing.