Thematic Bible: Of the shechemites against abimelech

When Abimelech had ruled over Israel three years, God sent an evil spirit between Abimelech and the lords of Shechem. They treated Abimelech deceitfully, so that the crime against the 70 sons of Jerubbaal might come to justice and their blood would be avenged on their brother Abimelech, who killed them, and on the lords of Shechem, who had helped him kill his brothers. read more.
The lords of Shechem rebelled against him by putting people on the tops of the mountains to ambush and rob everyone who passed by them on the road. So this was reported to Abimelech.