Best Buy CEO Brian Dunn has officially resigned from his post, the Wall Street Journal reports.

Dunn had been the popular electronics retailer's chief executive for three years, and he was with the company for 25 years before that. His resignation comes at a time when the company's future is uncertain and the threat of online competitors is at an all-time high.

Last month, Best Buy announced that it would close 50 big box stores around the country in an effort to cut costs. It also said it would lay off 400 workers in its corporate offices and seek an additional $800 million in budget cuts.

In addition to a new CEO, Best Buy is mulling a new business model built around smaller retail outlets with a more limited selection of goods. Two such stores are currently planned to open in San Antonio and Minneapolis.

[via WSJ]