Senate investigators indicated Monday they’ve received few answers from the Obama administration after a laptop and portable hard drives – likely containing names and Social Security numbers of millions – were stolen from a federal building in Washington state.

Sen. Ron Johnson of Wisconsin, the Republican chair of the Senate government affairs panel, asked Health and Human Services Secretary Sylvia Burwell on Monday if the drives stolen from the federal Office of Child Support Enforcement in Olympia, Washington, were ever recovered.

“It is unclear from the information HHS provided how many of those children’s records were compromised, and the potential risk to those children, despite a statutory requirement that you provide that information to Congress,” Johnson said in a letter obtained by The Associated Press.

The data breach would mark the latest case of personal information swiped from the federal government. Last year, the Office of Personnel Management said hackers stole data in an unprecedented breach of private data for millions of federal workers.

Court documents stated the stolen drives had between 2 million and 5 million individual profiles containing names, Social Security numbers, birthdates, addresses and phone numbers. Police said the intruders used a copy of a building key kept by a former building employee, who was ultimately fired for stealing.

The Office of Child Support Enforcement oversees child-support programs across the nation. One suspect told police he was inside the building for two hours during the burglary, when $600 in cash and a government credit card were also taken.

Johnson asked Burwell what specific information was on the hard drives, when officials first became aware of the burglaries and if they’ll notify those whose data were stolen. He also said the Obama administration hasn’t provided enough answers on whether other data were stolen from HHS, which keeps national databases on child abuse and neglect.

An HHS spokeswoman acknowledged Monday that the stolen equipment may have contained personally identifiable information, adding the incident was a property theft and not an intrusion of federal networks.

“If the hard drives are accessed, there would be a large data breach,” Thurston County, Washington, prosecutors said in court filings last week. It was unclear if the drives were encrypted, which would make it harder for thieves to copy data.

Olympia police said they’ve arrested two in connection with the thefts, including 28-year-old Nicholas Perring, who was charged with second-degree burglary and had bail set at $10,000. The other, Demario Heard, was also arrested on suspicion of meth possession.

Perring told investigators he and Heard split the $600, found in a bag, to go gambling. Police later reported camera equipment missing from a separate Federal Highway Administration office in the building, as well as Nintendo video games from a nearby business.

The Federal Protective Service declined to comment on the case, citing an ongoing investigation.

In the federal OPM hack last year, more than 21 million Social Security numbers and other sensitive information were compromised, believed to be the biggest in U.S. history. OPM later offered credit-monitoring services and identity-theft insurance to those affected.

(AP)