 In order to cut off the route of their raids, Wei sent his officer Yao Yue (姚岳) to build a fort near the Fen River.Yao initially was fearful that as his troops were building the fort that Northern Qi would launch an attack against him, but Wei warded off Northern Qi attacks by setting up bonfires in the surrounding hills, making Northern Qi forces believe that Yao was being reinforced by a large army, and therefore did not attack Yao, allowing Yao to complete the fort.In 564, Wei helped negotiate an agreement where Northern Qi returned Yuwen Tai's sister and sister-in-law (Yuwen Hu's mother) to Northern Zhou in exchange for peace.