On July 4 and 5 the Finnish Navy, supported by several German AFP gunbarges, made several raids on Viborg Bay in an attempt to disrupt the Soviet landings on the islands. Heavy Soviet resistance from shore artillery, numerous Motor Torpedo Boats, (MTB)s, and the Soviet air force forced the Finns to withdraw without reaching the intended target area. Although none of the Finnish ships were sunk, most of them suffered casualties among their crews and were badly damaged, requiring immediate repairs. This situation effectively forced Finnish naval forces to withdraw from the battle. Of the Finnish ships, the worst damage was suffered by the auxiliary gunboat "Viena" during a Soviet air attack on its anchorage. The ship came close to sinking but was still able to return to Helsinki for repairs.