Police have opened an attempted murder investigation after a man was shot just before 5 a.m. in Kalihi. The victim flagged down help at the Kapalama Post Office. Paramedics transported an 18-year-old man who had been shot multiple times to a trauma center. He was in serious condition.  Police are looking for a black or dark green four-door lowered Honda. Two men were in the front and a man in the back was believed to have the weapon.   No arrests have been made.