The U.S. online retailer Zulily is closing down, surprising customers and laying off hundreds of workers after efforts to salvage the business failed.

The Seattle-based company said in a notice on its website that it had tried to fill all pending orders and expected to manage that within the coming two weeks.

Zulily said it was trying to ensure that orders that could not be filled were canceled and refunded and offered a contact for customers who did not get their orders or refunds.

"This decision was not easy nor was it entered into lightly. However, given the challenging business environment in which Zulily operated, and the corresponding financial instability, Zulily decided to take immediate and swift action," said the notice, signed by Ryan C. Baker, vice president at management consultant Douglas Wilson Companies, which is handling the receivership for the company.

Founded in 2010 by Darrell Cavens and Mark Vadon, Zulily made a splash with products catering to families with young children and staged a successful IPO on the Nasdaq in 2013. It went private after QVC parent company Qurate, formerly Liberty Interactive, acquired Zulily in 2015 for $2.4 billion.

Zulily's CEO, Terry Boyle, left the company at the end of October as financial troubles mounted after private equity firm Regent acquired Zulily from Qurate in May.

The company's liquidation followed several rounds of layoffs as Zulily struggled to compete with Amazon. Earlier this month, Zulily sued Amazon in federal court. In the lawsuit, Zulily alleged that the retail giant "set out to 'destroy' Zulily" through pricing practices, The Wall Street Journal reported. Amazon called Zulily's accusations false, WSJ said.

Instead of declaring bankruptcy, Zulily is using an alternative for winding down the business known as an Assignment for the Benefit of Creditors, or ABC. The company has transferred all its assets and business in trust to Zulily ABC, LLC, to pay creditors out of proceeds from selling them.