The Drug Enforcement Administration plans to return a man’s life savings that the agency seized from his daughter at an airport over the summer, according to a letter from the agency, but it provided little explanation about why the more than $82,000 in cash was taken or why it was being given back.

Rebecca Brown said that she was never told she was under suspicion of a crime, that no drugs or other contraband were found during a search of her bag and that neither she nor her father have been charged with any crime since a DEA agent took the money at Pittsburgh International Airport as she was on her way to Boston in late August.

Brown and her father, Terry Rolin, filed a class-action lawsuit against the DEA, the Transportation Security Administration and government officials in January, saying the agencies violate the Constitution’s ban on unlawful searches and seizures by confiscating cash from travelers without probable cause to suspect that a crime has been committed. The lawsuit claims the DEA’s only criterion for confiscating cash is that it exceeds $5,000.

It is legal to travel domestically with any amount of cash, but travelers going abroad must declare amounts of more than $10,000.

On Feb. 28, an attorney for Brown and Rolin received a letter from a DEA lawyer saying the money was being returned. “After further review, a decision has been made to return the property,” the letter read, but it provided no additional explanation.

A DEA spokeswoman did not respond to a request for additional comment.

Brown said in an interview Wednesday she was relieved the money would be returned because her father, who is 79, has had to put off critical dental care and has not been able to repair his pickup truck. Still, she was angry the agency did not shed more light on the incident.

“There’s zero explanation and zero apology,” Brown said. “It’s unfortunate the government is able to do this to people. It’s just not fair.”

Dan Alban, a lawyer at the Institute for Justice, which is representing Brown and Rolin, said the lawsuit will continue because the institute is still getting reports that the DEA is seizing money at airports on flimsy pretexts.

Alban said DEA’s returning the money “confirms there was no probable cause for a seizure.”

“I think they realized: What were these guys doing?” Alban said of the seizure. “There was no evidence of criminal activity. It demonstrates there was nothing supporting the seizure.”

Brown said the episode began after a visit she made to her father’s Pittsburgh-area home, during which he asked her to open a joint bank account with him. Rolin kept his savings in cash, a habit he had picked up from his parents, who had lived through the Great Depression.

Brown said she got the money on a Sunday night and was leaving the Pittsburgh area for her home in the Boston area on a flight the next morning, before banks opened. Brown said she tucked the money into her carry-on and planned to open the account when she got home.

After a security scan, a DEA agent stopped her at the gate just minutes before her flight was to leave, she said. The agent quizzed her about why she was carrying so much cash. Brown put Rolin on the phone to confirm the story about opening a bank account, but he was unable to confirm certain details because he is experiencing cognitive decline.

“He just handed me the phone and said, ‘Your stories don’t match,’ ” Brown recalled the agent’s saying. “ ‘We’re seizing the cash.’ ”

Brown was stunned, and she eventually approached the Institute for Justice for help, sparking the lawsuit.