Amazon.com Inc. is closing all 87 of its pop-up stores in the United States, the Wall Street Journal reported on Wednesday, citing a company spokeswoman.

The closings are expected by the end of April, the WSJ report said, citing some of the employees at the stores.

Amazon is ending the retailer’s yearslong experiment with these small shops as the company tinkers with an evolving bricks-and-mortar strategy, the Journal reported. 

The company’s shares (AMZN) fell 1.2 percent to $1672.94 in afternoon trading. 

The company has pop-up stores in places everywhere from Whole Foods to malls and department stores, which prominently feature its Echo and Kindle devices.

Amazon also has similar stores in number of European countries, opening its first in Spain in November.

The news underscores how the online retailer is still working out its brick-and-mortar strategy.

Pop-up stores for years helped Amazon showcase novel products like its voice-controlled Echo speakers, but the company is now able to market those products and more at its larger chain of Whole Foods stores, acquired in 2017, and cashierless Amazon Go stores, which opened to the public last year.

The online retail giant will also open more “4-star stores” - stores that sell items rated 4-stars or higher by Amazon customers, the spokesperson added.

“After much review, we came to the decision to discontinue our pop-up kiosk program, and are instead expanding Amazon Books and Amazon 4-star, where we provide a more comprehensive customer experience and broader selection.”

Shares of bookseller Barnes & Noble Inc. (BKS) fell 8.4 percent after the report.