Mobile carrier T-Mobile said Sunday it is investigating a claim made in an online forum that the personal data of over 100 million users was breached.

The breach was first brought to attention by media outlet Vice, which reported the claims Sunday.

According to The Vice Motherboard website, "data includes social security numbers, phone numbers, names, physical addresses, unique IMEI numbers, and driver licenses information, the seller said. Motherboard has seen samples of the data, and confirmed they contained accurate information on T-Mobile customers."

The online forum post by the hacker states that they are asking for 6 bitcoin ($270,000) to stop the personal information from being released and sold.

"We are aware of claims made in an underground forum and have been actively investigating their validity. We do not have any additional information to share at this time," a T-Mobile spokesperson told Reuters in a statement.

T-Mobile declined to answer questions about the breach.

The information could have possibly been slightly stopped by T-Mobile, the alleged hacker suggested. "I think they already found out because we lost access to the backdoored servers," the hacker said. "It's backed up in multiple places."

The name of the forum where the claim was posted is unknown.