A former firefighter who allegedly drove eight hours armed with a cache of weapons was “ready for war” and intended to kill his ex-girlfriend’s family after she ended their relationship, prosecutors said at a hearing Friday. Brian J. Lanzim, 37, was ordered held in the Ocean County Jail pending trial after Judge Pamela M. Snyder called the allegations “extremely concerning” and “extremely violent in nature.” Authorities say Lanzim drove from Bangor, Maine , to South Toms River on April 29 with guns, ammunition and a bulletproof vest after learning his ex-girlfriend, who is also the mother of his two children, had filed for a temporary restraining order against him. “He was ready for war,” Assistant Prosecutor Mara Brater said during the hearing. “He armed himself with two firearms. He armed himself with a bulletproof vest. He had 15 large capacity magazines in his trunk.” Prosecutors allege Lanzim intended to kill or seriously harm his ex-girlfriend’s family in an effort to gain custody of their children.…