WASHINGTON (AP) — President Donald Trump is going after Amazon again.

Trump tweeted Thursday: "I have stated my concerns with Amazon long before the Election. Unlike others, they pay little or no taxes to state & local governments, use our Postal System as their Delivery Boy (causing tremendous loss to the U.S.), and are putting many thousands of retailers out of business!"

Amazon shares dropped 4.4 percent Wednesday after Axios reported that Trump has wondered if there was a way to "go after" the company with antitrust or competition laws.

Amazon fought for years against collecting sales tax but now collects taxes nationwide. And while the Postal Service has lost money for years, online shopping has led to growth in its package-delivery business.