ROCKFORD (AP) -- A 19-year-old gang member was accused Saturday of fatally shooting a veteran gang unit officer, authorities said. William J. Buck was charged with first-degree murder in the death of Rockford police Detective Kevin Rice, 38, who was found dead in his car early Friday, Rockford Police Chief Jeff Nelson said. Under state law, a person charged with killing a police officer must be held without bail. Buck, a member of the Gangster Disciple gang, was arrested Friday night after a brief struggle on an unrelated battery charge, Nelson said. He said a person who was with Buck when Rice was shot was a key witness in the case. The second person was not charged. The murder weapon is still missing, Nelson said. In 1995, Buck pleaded guilty as a juvenile in the killing of a man on a Rockford street, Nelson said. He said Buck was freed some time during the past year. Rice was the first Rockford police officer to die in the line of duty in 21 years. A member of the police since 1987, he was married with three children and was on vacation when the shooting occurred. Funeral services will be at 11 a.m. Wednes-day at Macedonia Baptist Church. A memorial fund has been set up at Alpine Bank locations in the Rockford area.