In July 1855, the allied squadron tried to go past Taganrog to Rostov on Don, entering the Don River through the Mius River. On July 12, 1855 the H.M.S. "Jasper" grounded near Taganrog thanks to a fisherman, who repositioned the buoys into shallow waters. The cossacks captured the gunboat with all of its guns and blew it up. The third siege attempt was made August 19–31, 1855, but the city was already fortified and the squadron could not approach too close for landing operations. The allied fleet left the Gulf of Taganrog on September 2, 1855, with minor military operations along Azov Sea coast continuing until late fall 1855.