Excerpts from Books and Wikipedia
"An enraged mob of Venetian expats attacked and sacked the new Genoese quarter, tearing off roofs, knocking over walls, and leaving it uninhabitable. Manuel sent a sharp message to the Doge, Vitale Michiel, demanding that Venice both rebuild the quarter and pay damages to Genoa. The Doge refused, blaming the destruction on the citizens of Constantinople. Manuel had anticipated the refusal; he had already sent secret messages all across Byzantium, ordering his officials to arrest every Venetian citizen on Byzantine soil at one time. . . . This gave Manuel over ten thousand hostages to hold against future Venetian aggression. But Doge Vitale Michiel, apoplectic with fury, declared war anyway. The Venetians spent four months building a special war fleet to retaliate, and then set sail for Byzantine territory. . . . The Venetian camp at Chios was struck with plague; . . . Manuel continued to stall, the Venetians continued to die, and finally Vitale Michiel surrendered to the inevitable. He loaded the survivors onto his ships and staggered home. . . . This certainly proved true for Vitale Michiel; when he arrived in Venice, his angry subjects assassinated him for his failure."