Wood boring insects have been found during inspections of international commercial air cargo at detroit metropolitan airport in romulus. U.s. Customs and border protection said thursday that six inspections in late january turned up eight insects. The wood packaging materials they were in were refused entry into the country. Customs and border protection agricultural specialists also discovered tunnels made by insects in wood packaging on 13 occasions last month. The agency says the increased movement of wood products in international trade has allowed insects, other pests and pathogens to enter the u.s. From overseas. Invasive species have caused extensive damage to trees and agricultural products.