Several FBI employees stationed across Asia were recalled to Washington amid a probe into prostitution and partying, according to a report.

The Justice Department’s inspector general is looking into the allegations, which involve agents in about half a dozen cities in East and Southeast Asia, the Wall Street Journal reported. The employees were sent home in recent months as the investigation continues.

It’s still unclear exactly what the nature of the allegations are.

“Upon learning of these allegations of misconduct, action was taken to reassign certain personnel to non-operational roles while the allegations are reviewed,” the FBI said in a statement to the paper.

The agency has offices based at US embassies in cities around the world, where agents work with their foreign counterparts to fight international terrorism and look into FBI cases. The posts can last several years and can involve late-night drinking to build relationships with local officials.

Though prostitution is legal or tolerated in some of these countries, FBI officials worry that it could be a potential avenue for their agents to be compromised by foreign intelligence services.