Shares in American Apparel Inc. added more than 4 percent early Thursday after the retailer posted a 24 percent jump in same-store sales for May.

As of the end of the month, the Los Angeles-based clothing manufacturer and retailer said it had 144 stores in the sales comparison (which measures stores open more than 12 months) and for the month opened four retail locations, one each in New York; Las Vegas; Liverpool, England and Kelowna, British Columbia, Canada giving it a total of 186 stores.

The surge in sales was welcome news to investors after the retailer posted a 35 percent decline in first quarter net income about a month ago.

Shares in American Apparel were up 4.3 percent to $7.55 in early trading Thursday.