WASHINGTON — A new government report says that less than 1 percent of the 4,000-mile U.S.-Canada border is considered under the operational control of U.S. border officials.

The chairman of the Senate’s Homeland Security and Government Affairs Committee, Connecticut Independent Sen. Joe Lieberman, calls the report alarming. He released it with Maine Sen. Susan Collins, a Republican.

The report by the Government Accountability Office says Customs and Border Protection believes it can detect illegal entries, respond and deal with them on only about 32 miles of the northern border.

The GAO also found that border officials can detect illegal entries over only about one quarter of the northern border.