WASHINGTON — Tom Marino, the Pennsylvania congressman who was President Trump's nominee for drug czar, withdrew Tuesday, less than two days after reports that legislation Marino backed restricted the enforcement of opioid laws.

Hours later, the Justice Department announced it is reviewing whether to seek a repeal of 2016 legislation supported by the drug industry — and Marino — that ultimately undermined the ability of law enforcement officials to stop suspicious shipments of opioids that have been driving surges in overdose deaths across the country.

"Rep.Tom Marino has informed me that he is withdrawing his name from consideration as drug czar," Trump tweeted Tuesday morning. "Tom is a fine man and a great Congressman!"

Deputy Attorney General Rod Rosenstein said Tuesday that he was "very concerned about" the law. "We're going to review it."

The announcements came after 60 Minutes and The Washington Post reported on Sunday that, as a U.S. House member from Pennsylvania, Marino was the key lawmaker behind legislation that made it virtually impossible for the Drug Enforcement Administration to freeze suspicious narcotics shipments from drug companies.

His nomination to head the Office of National Drug Control Policy was controversial even before the Post/60 Minutes exposé. Treatment advocates have highlighted Marino's push to lock up low-level drug users against their will, until they agree to treatment.

"One treatment option I have advocated for years would be placing non-dealer, nonviolent drug abusers in a secured hospital-type setting under the constant care of health professionals," Marino said at a May 2016 hearing. "Once the person agrees to plead guilty to possession, he or she will be placed in an intensive treatment program until experts determine that they should be released under intense supervision."

He suggested criminal charges would be dropped once the person completed treatment. "The charges are only filed to have an incentive for that person to enter the hospital-slash-prison, if you want to call it," Marino said.

Sen. Joe Manchin, D-W.Va., who had called for Marino's withdrawal on Monday, applauded the move Tuesday, thanking Trump on Twitter "for recognizing we need a drug czar who has seen the devastating effects of the problem."

Acting DEA Administrator Robert Patterson also acknowledged Tuesday that the Marino legislation “did impact” the agency’s efforts to stop suspicious opioid shipments, adding that it made investigators’ work “more challenging.’’

Patterson, however, took issue with the suggestion that federal authorities slowed their efforts to block the flow of the drugs.

He said the agency used other tactics when the law made it more difficult to halt suspicious shipments.

“We did not stop what we were supposed to be doing at DEA,” Patterson said.

In a statement Tuesday evening, Marino defended himself and the 2016 law, saying his record was distorted by "false accusations and unfair reporting." He said the law was a "balanced solution" to make sure people had access to medications they needed while also allowing the DEA to prevent the abuse of prescription drugs.

Marino said he withdrew "to remove the distraction my nomination has created to the utterly vital mission" of the drug policy office.

Trump struck an equivocal note about Marino's future on Monday when asked about the news reports on the congressman's relationship with the drug industry,

"As far as Tom Marino, so he was a very early supporter of mine, the great state of Pennsylvania," Trump told reporters at the White House. "He's a great guy. I did see the report. We're going to look into the report. We're going to take it very seriously."

Trump, who has pledged to unveil a national plan to combat opioid policy for months, said he will make "a major announcement, probably next week, on the drug crisis."

Contributing: Deirdre Shesgreen