The recruits have had criminal backgrounds or failed drug tests or were unable to meet physical or academic standards, raising concerns about the agency’s rush to hire immigration officers, sources told NBC News.

Immigration and Customs Enforcement has placed new recruits into its training program before they have completed the agency’s vetting process, an unusual sequence of events as it rushes to hire federal immigration officers to carry out Donald Trump’s mass deportation policy, a current and two former Homeland Security Department officials told NBC News.

ICE officials only later discovered that some of the recruits failed drug testing, have disqualifying criminal backgrounds or don’t meet the physical or academic requirements to serve, the sources said.

Staff members at ICE’s training academy in Brunswick, Georgia, recently discovered one recruit had previously been charged with strong-arm robbery and battery stemming from a domestic violence incident, the current DHS official said. They’ve also found as recently as this month that some recruits going through the six-week training course hadn’t submitted fingerprints for background checks, as ICE’s hiring process requires, the current and former DHS officials said.