Border Patrol agents in southern California are unhappy after a faulty background check meant they unwittingly protected a “cartel wedding” last month, San Diego Union-Tribune reported. A feel-good moment during a “rare opening” of the gate at the San Ysidro Port of Entry turned to Border Patrol frustration as the agency worked to figure out how this was allowed to happen.

Brian Houston married his Mexican partner at the border crossing between California and Mexico in November through the Border Angels program, a non-profit that arranges visitations between people on opposite sides of the fence who cannot cross over for any legal reason. Border Angels notably does not handle background checks for these occasions, leaving that to Border Patrol. Houston’s wedding was the sixth such event at the border since 2013.

According to the Union-Tribune report, it may be more difficult to arrange further visitations because the initial background check failed to notice that Houston is a drug smuggler, hence the need for a wedding on the border. Back in February, Houston was arrested for attempting to smuggle dozens of pounds of heroin, cocaine and meth, charges for which he pled guilty. He had not been sentenced for these crimes yet, but Border Patrol did not know any of this until after the wedding took place.

Houston said the wedding showed “love has no borders,” but Border Patrol did not have the same rosey view of the incident. National Border Patrol Council Local 1613 spokesman Joshua Wilson said his agents felt they had been “duped.”

“Turns out we provided armed security for a cartel wedding,” Wilson said.

Smuggling drugs back and forth between the U.S. and Mexico has been a contentious problem for years, as Mexico’s drug war has killed an estimated tens of thousands of people since 2006. On Oct. 27, Border Patrol agents apprehended a big-name cartel leader known as “Cadete” at the San Ysidro border crossing, mere weeks before Houston’s cartel wedding, according to the Department of Justice.