LOS ANGELES—Four people have now been arrested in connection with the shooting death of an off-duty Los Angeles Police Department (LAPD) officer, authorities said Jan. 12. The officer, 27-year-old Fernando Arroyos, a three-year veteran of the LAPD, was shot about 9:15 p.m. Monday in an apparent exchange of gunfire with as many as three armed robbery suspects in the unincorporated Firestone-Florence neighborhood in the 8700 block of Beach Street. He died at a hospital. Following the crime, five suspects were detained Tuesday for questioning — and four of those have now been arrested, according to the Los Angeles County Sheriff’s Department, which is handling the investigation into the killing. “We’ve been working around the clock on this case … working hand-in- hand with LAPD,” LA County Sheriff Alex Villanueva said Wednesday morning. Referencing the arrests, he added, “Going to bring some people to justice.” The names of the four suspects …