The professor, named only as M Sefik I, first lost his elder son, a dentistry student at Hacettepe University in Ankara, who on March 10 sent his parents a message asking them to pray for him before leaving Turkish territory.
The elder son then helped his 16-year-old twin brothers to cross the Turkish border to Syria, the paper added.
Turkey's National Intelligence Agency (MIT) has informed the family the three are believed to have first gone to Syria and then to Iraq to fight with the IS jihadists.
"We taught them to be human beings. We do not know how they arrived at that stage," said the father, whose place of work and full name was not given by the paper.
According to Hurriyet, over 2,300 Turks are believed to have joined the ranks of IS militants who have taken swathes of Iraq and Syria up to the Turkish border.
Turkey has also been criticised for not doing enough to halt the flow of foreign jihadists across its borders but Erdogan said today 1,700 would-be foreign militants have been detained and deported.
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