By Brendan Sasso - 06/06/12 09:20 PM EDT
LinkedIn also said it has implemented new security measures to protect its users' personal information.
"We sincerely apologize for the inconvenience this has caused our members," Vicente Silveira, an engineering director for LinkedIn, wrote in a blog post. "We take the security of our members very seriously."
Silveira said the company is continuing to investigate how the breach occurred.
Sen. Patrick LeahyPatrick LeahyOvernight Tech: Obama signs FOIA reform bill | Musicians take YouTube fight to Europe | Feds probe first driverless car death Obama signs bill to expand access to federal records Dems leery of Planned Parenthood cuts spark Senate scuffle MORE (D-Vt.) and Rep. Mary Bono Mack (R-Calif.) expressed concern about LinkedIn's breach and said the incident shows the need for Congress to pass data security legislation.