Best Buy (NYSE: BBY) swung to a loss in the fiscal 2012 fourth quarter, as well as the full year, leading the world's largest consumer electronics retailer to plan to shutter 50 big box stores in the coming year, the company reported Thursday.

The news sent shares down during morning trading $2.13, or 8 percent, to $24.45.

The Minneapolis, Minn.-based company reported a net loss of $1.7 billion, or $4.89 a share, for its fiscal 2012 fourth quarter ended March 3, compared with a net income of $651 million, or $1.62 a share, in the year-earlier quarter.

Operating income for the quarter was $69 million, down from $1.13 billion in the fiscal 2011 fourth quarter.

Excluding one-time events, operating income was $1.36 billion, up 6 percent from $1.28 billion during the year-earlier quarter.

The quarter saw a bevy of one-time charges that totaled $2.6 billion, including Best Buy's purchase of Carphone Warehouse Group's share of Best Buy Mobile on Nov. 7, 2011.

The shuttering of stores nationwide is part of a broader effort to reduce costs by $800 million by fiscal 2015.

Revenue in the quarter rose to $16.63 billion, up 3 percent from $16.08 billion in the same quarter last year.

The number of shares outstanding was lower for the fiscal fourth quarter, as well as the full year. than in the year-earlier periods.

The net loss for the full fiscal 2012 was $1.23 billion, or $3.36 a share, down from a net income of $1.28 billion, or $3.08 a share, in fiscal 2011.

The company projected adjusted earnings per share in 2013 between $3.50 and $3.80, with revenue between $50 billion and $51 billion.