A sign with a DEA badge marks the entrance to the U.S. Drug Enforcement Administration (DEA) Museum in Arlington, Virginia, August 8, 2013. (© Jonathan Ernst / Reuters/REUTERS)

The Justice Department sent a memo to all its employees Friday warning them that soliciting prostitutes is a violation of department policy, whether off duty or on. The caution follows recent allegations that Drug ­Enforcement Administration agents had “sex parties” with prostitutes hired by local drug cartels in Colombia.

“Regardless of whether prostitution is legal or tolerated in a particular jurisdiction,” Attorney General Eric H. Holder Jr. wrote, “soliciting prostitutes creates a greater demand for human trafficking victims and a consequent increase in the number of minor and adult persons trafficked into commercial sex slavery.”

Justice Department officials will also review the security clearances of the DEA agents accused of engaging in sexual misconduct in Colombia to ensure that they do not present a security risk. The agents could be suspended or fired, an official said.

The department will also review the way the DEA conducts investigations to determine whether it is appropriately holding employees accountable when allegations are substantiated.

A report two weeks ago by Justice Department Inspector General Michael Horowitz found that 10 DEA agents working in Colombia attended the sex parties. Seven of the 10 agents admitted to being at the parties, most of which took place at an agent’s “quarters,” which was leased by the U.S. government.

The investigation followed the 2012 prostitution scandal in Cartagena, Colombia, involving Secret Service agents. One Secret Service advance agent implicated in that scandal told investigators he met with a prostitute as a result of an informal party that DEA agents hosted with Colombian women, according to officials briefed on the inquiry.

Former police officers in Colombia also alleged that three DEA supervisory special agents were provided money, expensive gifts and weapons from drug cartel members, according to the inspector general’s report.

“Although some of the DEA agents participating in these parties denied it, the information in the case file suggested they should have known the prostitutes in attendance were paid with cartel funds,” according to the 131-page report.

Some of the agents involved received suspensions of between two and 10 days.

“Department leadership takes very seriously the allegations laid out in the IG’s report and acted quickly to remind all employees that they are prohibited from participating in commercial sex acts and will be suspended or terminated for violating the policy,” Justice Department spokeswoman Emily Pierce said.

She said the rule applies at all times for Justice Department employees, including while off duty or on leave, and it doesn’t matter whether the activity is legal or tolerated in a particular jurisdiction, foreign or domestic.

One DEA official had told an investigator for the inspector general that “prostitution is considered part of the local culture [in Columbia] and is tolerated in certain areas called ‘tolerance zones.’ ”

A Justice Department official said that after Horowitz’s report was released, Holder and Deputy Attorney General Sally Yates discussed the issue. According to a Justice Department official, who spoke on the condition of anonymity to discuss an ongoing review, both Holder and Yates believe the disciplinary process at DEA was “inadequate.”

They decided not to replicate the original investigation but to review security clearances and take that probe out of the hands of the DEA; instead it will be conducted by the Justice Department’s Security Office, the official said.

Holder has also directed the Justice Department’s Office of Professional Responsibility to examine the internal DEA inquiry and make recommendations about how to improve the investigative and disciplinary process, Pierce said.

DEA Administrator Michele Leonhart is scheduled to testify before the House Committee on Oversight and Government Reform on Tuesday.