Federal drug agents conducted surprise inspections of NFL team medical staffs on Sunday as part of an ongoing investigation into prescription drug abuse in the league. The Post's Sally Jenkins explains what happened and why. (Tom LeGro/The Washington Post)

Five NFL teams that were subject to surprise inspections by Drug Enforcement Administration agents following their games on Sunday described the questioning as brief and straightforward, and said no arrests were made.

As the teams returned to their football seasons, federal agents added to the paperwork in their months-long investigation into the way NFL franchises store, prescribe, track and distribute prescription medications and other controlled substances.

The Cincinnati Bengals and Detroit Lions confirmed Monday they were among the teams that met with DEA agents. Similar to accounts offered Sunday night by the San Francisco 49ers, Tampa Bay Buccaneers and Seattle Seahawks, team officials said the postgame inspections on the surface appeared to be uneventful.

Law enforcement officials have not released any details on what they learned from Sunday’s inspections, or precisely what they’d hoped to find. A spokesman for the U.S. Attorney’s office for the Southern District of New York, which is coordinating with the DEA, declined to comment on Monday.

A former prosecutor from that office cautioned against reading too much into a single operation, noting that agents and prosecutors typically spend months building a case. “What we saw yesterday was most likely the tip of the iceberg,” said Josh Berman, now a partner with Katten Muchin Rosenman’s Washington office.

Gritting through the pain (The Washington Post/Source: Washington Post survey of retired NFL players)

Berman was speaking in general about the office’s investigations and said he had not been briefed about the NFL case. Based on his experience in similar cases, Berman said investigators typically target physicians who are “excessive” in their prescription practices.

The U.S. Attorney’s office for the Southern District of New York has found plenty of success in recent years pursuing high-profile cases in which the targets have especially deep pockets. The office has procured more than $4 billion from criminal and civil cases since January 2013, largely in the form of hefty fines or forfeitures.

DEA spokesman Rusty Payne previously described Sunday’s inspections as “administrative,” as plain-clothed agents sought to determine whether NFL teams follow federal regulations governing the storing, transporting, labeling and dispensing of controlled substances. Doctors are required to have proper licensure in each state in order to carry, prescribe and distribute drugs.

The Bengals were met by investigators at Louis Armstrong International Airport in New Orleans after their victory over the Saints, a DEA spokesman said.

“Everything was in compliance,” Debbie Webber, a spokeswoman for the DEA’s New Orleans office, said. “Nobody was detained or arrested. They were following the right protocols and had all the right paperwork.”

The agents that met with Bengals officials were from the DEA’s New York office. Webber said the meeting in New Orleans was brief between team personnel and federal investigators, and the team was allowed to leave shortly after answering questions in a private room.

“The Bengals have never had any issues regarding prescriptions/controlled substances,” team spokesman Jack Brennan said in a statement. “We have a highly rated medical staff that handles these matters with concern for proper and legal practices. Any issues which might be present elsewhere are not present with our organization.”

The Lions were similarly questioned by federal agents following their loss Sunday at Arizona, the team said.

“Yes, from what I understand they did interview one of our doctors, and I know we were in compliance,” Lions Coach Jim Caldwell told WXYZ-TV in Detroit.

While the DEA had reason to visit with specific teams on Sunday, a law enforcement official with knowledge of the investigation said the scope of the case encompasses the entire 32-team league. Brian McCarthy, a league spokesman, confirmed Sunday evening that multiple inspections took place, and said the league had “no information to indicate that irregularities were found.”

The NFL Players Association has not commented on the inspections, though a union spokesman said “if called upon, the union would cooperate with the DEA.”

The DEA investigation was launched shortly after former players filed a class-action lawsuit in May. More than 1,300 plaintiffs are now part of the suit, alleging team medical staffs routinely violated federal and state laws by supplying players powerful addictive narcotics to help them play through injuries on game days.

“We have had a productive relationship with the DEA over the years,” Matt Matava, the St. Louis Rams’ team doctor and president of the NFL Physicians Society, said in a statement.