the korean navy attacked a japanese transportation fleet effectively and caused extensive damage. won gyun and yi sun-sin at the battle of okpo has destroyed the japanese convoy, and their failure enabled korean resistance in jeolla province, in the south-east of korea, to continue. wakisaka yasuharu was ordered to dispatch a 1,200 man navy during the keicho invasion and annihilated the invading korean navy led by won kyun during a counterattack in july 1597 (battle of chilcheollyang). korean admiral yi eokgi and won gyun of korea were killed in this combat. hansan island was occupied by japan, consolidating the japanese hold on the west coast of korea. to prevent japan from invading china by way of the korean peninsula west coast, china sent naval forces.