Honolulu police are assisting Big Island police with an second-degree assault case, involving a 2-month-old boy in Kona. Hawaii County police are calling it a "serious harm" case. The infant was airlifted to a Honolulu hospital Tuesday at 8 p.m. with head trauma. Big Island authorities are requesting help from Honolulu police in their investigation.  A police highlight lists a 32-year-old man as a suspect in the case, but no arrests have been made. An outside agency is also assisting in the investigation.