OTTUMWA, Iowa (AP) — An 18-year-old man already facing a murder charge has been accused of another shooting. Police have charged Jacob Heckethorn with attempted murder, saying he shot Clifford Collett Sr. on Aug. 16 in Ottumwa. Wapello County District Court records say Heckethorn already has pleaded not guilty to charges of first-degree murder and attempted murder in the original case. Police say he killed William Shettlesworth and shot at Dustin Greene on Aug. 23 in Ottumwa. Heckethorn is due back in court Sept. 17. He lives in Ottumwa.