An employee with MNsure, Minnesota’s new health-insurance exchange, e-mailed the names, addresses, and Social Security numbers of thousands of insurance agents to an insurance broker applying to be an Obamacare “navigator,” highlighting concerns many have expressed about the security of the law’s new exchanges.

The Star Tribune reports the employee accidently sent an e-mail containing the information of about 2,400 insurance agents to a local insurance broker. MNsure officials said once they realized the mistake, they called the broker and explained how to delete the information from his computer.

“The more I thought about it, the more troubled I was,” the broker who received the info said. “What if this had fallen into the wrong hands? It’s scary. If this is happening now, how can clients of MNsure be confident their data is safe?”

The broker and the MNsure employee had been e-mailing because the broker was interested in registering as a certified “navigator,” who will help sign up people to the exchanges when it opens October 1. Critics of the law have called on federal and state governments to address potential privacy concerns created by the navigators, who will have access to the personal information of those they’re signing up for the exchanges.

“It’s unsecured, on an Excel spreadsheet — which is using outdated technology to transfer that information in the first place,” the broker said. “They’ve got to realize they have a huge problem.”

MNsure said it is investigating the incident, but believes it was accidental.