The founder and chief executive of the Ashley Madison infidelity dating website, Noel Biderman, has stepped down.
A statement released by the firm said his departure was
"in the best interest of the company".
The senior management team will take over leadership until a new chief executive is appointed, it added.
Details of more than 33m accounts were stolen from the website, which offers people the chance to have an affair.
Avid Life Media, which owns the site, has offered a reward of C$500,000 (£240,000) for details about the Ashley Madison hackers.
Mr Biderman, a former sports lawyer, launched the website in 2001.
He said at the time that he wanted to offer the same opportunities for both women and men seeking extra-marital encounters.
The site's name was made up of the two most popular names for baby girls in the US at the time - Ashley and Madison.
Parent company Avid Life Media also owns other match-making websites including Cougar Life, Established Men, and The Big and the Beautiful.
"We are actively adjusting to the attack on our business and members' privacy by criminals. We will continue to provide access to our unique platforms for our worldwide members," the firm said.
"We are actively co-operating with international law enforcement in an effort to bring those responsible for the theft of proprietary member and business information to justice,
