As part of its efforts to combat terrorism, the state Highway Commission says that it`s installing surveillance cameras on two bridges that link Arkansas and Mississippi. The cameras are to go up on the U-S 49 bridge at Helena and the U-S 82 bridge near Lake Village. The bridges are two of about one thousand nationwide that are considered strategic crossings in need of closer scrutiny. State highway officials say they don`t think the cameras will prevent a terrorist attack, but that they will let them react more quickly if something should happen. Earlier this month, the Department of Homeland Security warned that terrorists may be planning to crash cargo planes from overseas into targets in the United States. The potential targets included nuclear power plants, bridges and dams.