A burgeoning East Boston-based street gang made up of alleged rapists and machete-wielding robbers has been linked to the al-Qaeda terrorist network, prompting Boston police to ``turn up the heat'' on its members, the Herald has learned. MS-13, which stands for La Mara Salvatrucha, is an extremely violent organization with roots in El Salvador, and boasts more than 100 ``hardcore members'' in East Boston who are suspected of brutal machete attacks, rapes and home invasions. There are hundreds more MS-13 gangsters in towns along the North Shore, said Boston police Sgt. Detective Joseph Fiandaca, who has investigated the gang since...