Less than 1 percent of the 4,000-mile U.S.-Canada border is considered under the operational control of U.S. border officials, according to a report released Tuesday by the Government Accountability Office.

"To me this report is absolutely alarming," said U.S. Sen. Joe Lieberman, I-Conn., chairman of the Senate Homeland Security and Government Affairs Committee, noting that there is more known terrorist activity in Canada than Mexico. "GAO makes clear defense of our northern border is weak."

Crossers include people seeking to immigrate illegally, criminals trafficking humans and smuggling drugs, and, potentially, terrorists, said U.S. Sen. Susan Collins, R-Maine, who released the report with Lieberman.

The GAO report 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. It says the Border Patrol was aware of all illegal border crossings on only 25 percent of the border, or 1,007 out of 4,000 miles.

Most areas of the northern border are remote and inaccessible by traditional patrol methods, the report said.

"Few northern border miles had reached an acceptable level of security as of fiscal year end 2010," said the report, citing Border Patrol security assessments. It also found that illegal crossings by terrorists are more likely along the northern border than they are across the southern border.

Collins said the Department of Homeland Security allocates increasing amounts of money to the southern border "to the detriment of the northern border." The money helps coordinate the federal government's border security efforts with state, local and tribal law enforcement agencies.

"It is very clear from this report that the United States remains very vulnerable," said Collins, who called the report shocking.

Lieberman said that while the resources aren't there to put people along the entire 4,000-mile northern border, "we ought to be able to detect people coming over." He said he wants federal officials to be able to dispatch law enforcement when they detect an illegal entry.

A Homeland Security spokesman said the agency has made critical security improvements along the northern border, such as deploying additional Border Patrol agents, technology and infrastructure. The spokesman, Matthew Chandler, added that the department is taking steps to address the GAO's recommendations.

In Canada, some members of Parliament dismissed American worries about security along the countries' border. Immigration Minister Jason Kenney said Canada has worked hard to improve security along the border, and there's no reason for added controls that would slow trade or travel between the two, The Canadian Press reported.


Gamboa reported from Washington.