(CNN) -- The CEO of popular messaging app Snapchat is apologizing after a set of filthy e-mails he wrote several years ago to his fraternity brothers at Stanford University was leaked publicly this week. In the e-mails, acquired by Gawker's Valleywag blog, Evan Spiegel encourages fellow Kappa Sigma members to get sorority women drunk enough to have sex, mocks another fraternity by suggesting its members are gay and refers to a different group of sorority members as "sororisluts." "Hope at least six girl[s] [performed a sex act on you] last night because that didn't happen for me," he wrote in one e-mail after a fraternity party, according to the Gawker blog.
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Snapchat's CEO apologizes for crude e-mails he sent while at Stanford
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The messages insult women and encourage getting them drunk for sex
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Evan Spiegel, 23, says he's "mortified" by the e-mails
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Snapchat is a photo-based messaging app with more than 30 million users
In a written response sent to CNN by @placeholder, Spiegel, now 23, apologized for the e-mails.