Nearly one-third of the cameras in the US Customs and Border Protection’s (CBP) primary surveillance system along the southern US border are unserviceable, according to an internal agency memo sent in early October. It means illegal immigrants have a better chance of crossing into the US undetected. “The nationwide issue is having significant impacts on [Border Patrol] operations,” reads a CBP memo sent to a sector of agents along the southern border and obtained by NBC News.

The failure affects about 150 out of the 500 cameras that can be found atop the surveillance towers that dot the US-Mexico border. The loss of capability is a result of “several technical problems,” the memo states. But those in authority at CBP, who spoke anonymously to CBS News, said the problem lies in old equipment that doesn’t get regular maintenance.

CBP is using a technology called Remote Video Surveillance Systems since 2011 to “survey large areas without having to commit hundreds of agents in vehicles to perform the same function.” But 30 percent aren’t performing any function and it’s not clear when the problem started. Two CBP officials revealed that although a few repairs have been initiated, there is a backlog of 150 more that have been flagged. Vast swaths of the southern border could be affected although the anonymous whistleblowers were not precise about the area affected.

A CBP spokesperson said the agency has installed 300 new towers that utilize newer technology. “CBP continues to install newer, more advanced technology that embrace artificial intelligence and machine learning to replace outdated systems, reducing the need to have agents working non-interdiction functions,” the spokesperson said.

The Border Patrol union in Laredo, TX shared the camera issue last week in a Facebook post, telling its members that it “shares your concerns that inoperable camera towers along the border are causing serious officer safety and border security concerns.”

“We hope this issue is resolved soon as the problem has been ongoing for quite some time!” the union added in the post, dated Friday. “The American taxpayer has made significant investments in technology along the border, and they expect that this technology is operational.”

The internal Border Patrol memo specifies that the blame for the camera outage lies with the Federal Aviation Administration (FAA), which, as the government organization would have it, is responsible for maintaining the border cameras.

CBP is assessing whether it makes better sense to replacing the FAA with a private contractor that can provision “adequate technical support for the cameras."

The report comes as immigration has been an issue of concern for voters amid in the 2024 presidential race. Democratic presidential candidate Vice President Kamala Harris has reiterated her support for a bipartisan bill introduced earlier this year that purported to reduce illegal immigration at the southern border. However, the bill would still have allowed at least 1.4 million illegal immigrants into the country every year.