Three killers of Jatiya Samajtantrik Dal (JSD) founding President Kazi Aref Ahmed and four other party men have been hanged 17 years after their killing.Kazi Aref was one of the key organizers of the Liberation War.Three killers Safayet Hossain Habib, Anwar Hossain and Rashedul Islam Jhontu were executed at Jessore Central Jail on Thursday midnight.Of the two remaining death row convicts, Elias Hossain died and Mannan Molla is absconding.Kazi Aref Ahmed and four others died after extremists opened fire during a rally on the grounds of Kalidashpur Primary School at Kushtia’s Doulatpur Upazila on February 16, 1999.The others killed in the incident are the then JSD unit President Lokman Hossain, General Secretary Yakub Ali, local JSD leaders Israil Hossain and Shamsher Mandal.The district’s Civil Surgeon Shahdat Hossain entered the jail at 9:30pm on Thursday.In this connection, Deputy Inspector General (prison) Tipu Sultan confirmed this to journalist.