Customs Security Gains Ground

WASHINGTON — The Customs Service’s mammoth effort to step up the security of the thousands of cargo containers that enter U.S. ports each day is gaining steam.

Since April, companies that import 34 percent of all U.S.-bound cargo have signed up to participate in a voluntary supply-chain security program called the Customs-Trade Partnership Against Terrorism. The program’s goal is to prevent a cargo container from being used to smuggle terrorist operatives or materials into the U.S.