Alappuzha (Kerala), Mar 15 (ANI): A youth Congress, Sunil Kumar, activist on Tuesday was hacked to death allegedly by some CPM youth wing Democratic Youth Front of India (DYFI) activists in Alappuzha, Kerala. According to the sources, the police have arrested four people in the murder case and are further probing the matter. Sunil Kumar is survived by his wife, seven-year-old daughter and parents.