SAN JUAN, Puerto Rico (AP) — The US Government announced Wednesday that it will detain all imports of sugar and related products made in the Dominican Republic by Central Romana Corporation, Ltd amid allegations that it uses forced labour.

A US Customs and Border Protection (CBP) investigation found that the company allegedly isolated workers, withheld wages, fostered abusive working and living conditions and pushed for excessive overtime, the agency said in a news release.

"Manufacturers like Central Romana, who fail to abide by our laws, will face consequences as we root out these inhumane practices from US supply chains," said AnnMarie Highsmith with the CBP's Office of Trade.

Central Romana said in a written response to The Associated Press that it received the news about the import ban with "great astonishment".

"In recent decades we have invested millions of dollars to improve the working and living conditions of our employees in agricultural areas, guaranteeing decent wages and increased benefits, training and education workshops, as well as training in human rights and duties of our workers," it said.

Central Romana, which has long faced those types of accusations, is the Dominican Republic's largest sugar producer in an industry that exports more than US$100 million worth of products to the US every year.

One of Central Romana's owners is the Florida-based Fanjul Corp.

The announcement was cheered by activists who have long decried the treatment of tens of thousands of workers who live and work on sprawling sugar cane fields, many of them Haitian migrants or descendants of them.

"This is needed to improve their situation," Roudy Joseph, a labour rights activist in the Dominican Republic, said in a phone interview. "We've been asking for improvements for decades."

The Associated Press last year visited several sugar cane fields owned by Central Romana where workers complained about a lack of wages, being forced to live in cramped housing that lacked water, and restrictive rules including not being allowed to grow a garden to feed their families since transportation to the nearest grocery store miles away was too costly.

Joseph noted that at least 6,000 workers also are demanding pensions for which they paid dues but that were suspended by Dominican President Luis Abinader.

Sugar cane workers also have organised several protests this year to demand permanent residencies after working for decades in the Dominican Republic, which is now cracking down on Haitian migrants under Abinader in a move that has drawn heavy international criticism.

Central Romana produced nearly 400,000 tons (363,000 metric tons) of sugar in the harvest period that ended last year after grinding more than 3.4 million tons (3 million metric tons) of cane, according to the company.

Wednesday's announcement comes after the US Department of Labor in September placed sugar cane from the Dominican Republic on its list of goods produced by children or via forced labour. The US State Department also has cited the Dominican Republic in its report on human trafficking.

A group of US legislators who visited the country issued a statement in July saying workers lived in settlements, or bateyes, "under harsh and substandard conditions" and that some "described being directed to stay quiet and not speak to anyone about their conditions before our visit".

The congressional delegation also noted that Central Romana had started to make improvements but that "despite this, a culture of fear appears to permeate the industry, where company supervisors, armed guards, and officials from an unrepresentative union monitor workers both in the fields and in the bateyes".