 Complete the following phrase:  This area was attacked by the Ottomans in 1461 for the first time. In October 1483, near the Dubica, the army of Knyaz Bernardin Frankopan defeated the regional Ottoman forces in the Battle of Una. In 1513, the Ottomans attacked the border zone again and occupied Dubica. On 16 August, Croatian Army led by Ban Petar Berislavić clashed with the Ottoman army forces between the Sava and Una rivers and won a great victory over them in the Battle of Dubica. Estimates of Ottoman casualties range from over 2,000 to 7,000 killed, drowned while fleeing, and imprisoned, together with a large number of freed Christian captives. Among them, there were four army commanders killed and one captured. After the battle, Berislavić was named as Count of Dubica and Prior of Vrana by King of Hungary and Croatia Vladislaus II. In 1538, during the 