Sheryl Sandberg took to Facebook on Wednesday to address the harsh criticism the social network faced after reports surfaced that it didn't protect user data. While she didn't apologize, she vowed to investigate the ways partnering apps collect and use customer information.

"We know that this was a major violation of people's trust, and I deeply regret that we didn't do enough to deal with it," Sandberg, the COO of the company, wrote in a Facebook post. "We have a responsibility to protect your data--and if we can't, then we don't deserve to serve you."

Sandberg's post came less than a week after The New York Times and The Observer of London reported that Cambridge Analytica, a political data company created by Stephen Bannon and Robert Mercer, gathered users' Facebook data and claimed it could influence the behavior of American voters. These methods were used in Trump's presidential campaign, but the effectiveness is unknown at this time.

Sandberg echoed the sentiments of Mark Zuckerberg, who also posted about Cambridge Analytica on Wednesday, giving readers a timeline of the events and outlining how he plans to tackle the situation.

In addition to investigating the apps that collected user information, Sandberg said the company will ban developers that misuse information and notify the people who were affected. What's more, the social network will reduce the amount of data customers give an app when they use Facebook to login.

While Sandberg and Zuckerberg both waited four days to address the report, their messages were clear: They plan to respond and change the company's policies to better protect customers. "Your trust is at the core of our service," Sandberg wrote. "We know that and we will work to earn it."