HOUSTON (AP) — The arrest of a Border Patrol supervisor on allegations that he killed four women calls new attention to the agency's problems keeping rogue officers off its force as it faces intense pressure to hire thousands more agents.

Juan David Ortiz, who worked in the agency's Laredo sector, is accused of targeting women believed to be prostitutes in what prosecutors say is the work of a serial killer.

The Border Patrol and prosecutors portrayed Ortiz as an outlier who is not representative of the thousands of employees working for the agency around the country.

"I would hate for this to...