A Linden man was arrested Friday and charged with the fatal shooting that took place in the Roselle area of Warinanco Park last weekend, authorities said. Gerald O. Walker, 47, was charged with murder and two weapons-related offenses, the Union County Prosecutor’s Office said in a release. The investigation began at 7:51 p.m. on May 19 when police were called to the park for a reported shooting, the office said. When they arrived they found a man, identified Friday as 29-year-old Linden resident Shakiir Manns, dead, investigators said. On Wednesday, authorities asked for the public’s help in f…