WASHINGTON – FBI agents added their voices to the thousands of federal employees Thursday calling for an end to the government shutdown, asserting that the bureau's diminished resources put national security and investigative operations at risk.

Thomas O'Connor, president of the FBI Agents Association, said an estimated 5,000 of the bureau’s 35,000 agents, analysts, lawyers and other personnel had been furloughed, limiting support for some surveillance and laboratory operations.

With the agency – and other federal workers affected by the shutdown – facing the prospect of missing a paycheck Friday, O'Connor said the burden could weigh most heavily on agents who are required to meet their financial obligations to maintain security clearances necessary for their work.

"Financial security is national security," O'Connor told reporters, adding that the ongoing shutdown was "entering uncharted territory" as the longest suspension of government operations in history.

In a petition to lawmakers and other government leaders, the agents’ group said the personal financial disruption "could even disqualify agents from continuing to serve in some cases" because of the potential damage to their clearance status.

The continuing financial "uncertainty" also was jeopardizing the agency's capacity to recruit new agent candidates and retain existing agents, analysts and lawyers.

"The ongoing financial insecurity caused by the failure to fund the FBI could lead some FBI agents to consider career options that provide more stability for their families," the petition said.

Agents went public with their grievances as President Donald Trump traveled to the southern border Thursday to rally support for the $5.7 billion he has requested for construction of a border wall.

Trump promised during his 2016 campaign that Mexico would pay for the construction, but he has since called for taxpayers to foot the bill. Congressional Democrats oppose any funding for a physical wall.

O'Connor declined comment on specific investigations that could be compromised, but he said backlogs in laboratory analyses that also support local law enforcement inquiries are all but certain to result.

While some federal agencies, including the Transportation Security Administration, were reporting an increased number of employee sick calls during the shutdown, O’Connor pledged that agents would not be among that number.

“Whether paid or not, we’re going to show up and do our job to the best of our ability,” O’Connor said.

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