Siege of Sredets

After a temporary lull following 1373, the Ottomans resumed hostilities in 1380. With a vast army, Sultan Murad advanced towards the southwestern parts of the Tsardom of Tarnovo, intending to capture the stronghold of Sofia. After bloody clashes in the valley of the Zlatitsa River, the Turks moved towards Sofia and began a siege. Under Ban Yanuka's command, the city fought bravely and repelled every attack by the superior Ottoman forces led by Lala Shahin.

Lala Shahin was unable to continue the siege and was forced to return to Edirne, where he informed the sultan of the failure. In his absence, the Turks resorted to deception to gain entry to Sofia. A Bulgarian convert to Islam captured Ban Yanuka while he was hunting and sent him to Lala Shahin in Plovdiv. From there, the Bulgarian commander was brought back to Sofia. When the defenders saw their captured leader, they surrendered the city to the enemy.