At the same time, Nikola Zrinski, Croatian ban and brave and skillful warrior, well-known all over Europe, demanded support from the Viennese court to consolidate and reinforce the border line in northern Croatia, by constructing new fortifications that would parry and neutralize the Ottoman threat from Kanije Eyalet in the occupied southwestern Hungary, but with no success.

As the siege of Novi Zrin was ongoing, Crimean Tatars led by kahn's son Ahmed Giray raided the Croatian countryside, which according to Evliya Celeby's Seyahatnâme resulted in sack of Krapina.

After a few weeks of fighting, with exhausted defenders receiving only insignificant reinforcements from the Emperor's headquarters, the Turks managed to dig lagums, or tunnels, below the bastions and ignited gunpowder to blow them up.

Ottoman commanders gave the order to their soldiers to destroy Novi Zrin completely to the ground and then marched their army northwards, first towards Kanije and then towards Saint Gotthard.

The destruction of Novi Zrin, together with a little bit later (on 10 August 1664) signed the Peace of Vasvár, that was recognized by many Croatian and Hungarian magnates like Zrinski as unfavourable and shameful.