President Donald Trump denied on Thursday that 3,000 people died last year in Puerto Rico as a result of Hurricane Maria, contradicting the findings of an academic report, while accusing Democrats of manipulating the data for political goals.

"3000 people did not die in the two hurricanes that hit Puerto Rico. When I left the Island, AFTER the storm had hit, they had anywhere from 6 to 18 deaths. As time went by it did not go up by much," Trump said on Twitter.

"Then, a long time later, they started to report really large numbers, like 3000," the president added.

Trump accused the Democrats of manipulating the data to make him "look as bad as possible," claiming that if "a person died for any reason, like old age," they were added to the death toll.

A recent study by researchers from George Washington University, commissioned by Puerto Rico's government, estimated that at least 2,975 people died as a result of Hurricane Maria, including many who died in the aftermath of the storm due to health crises caused or aggravated by the lack of electricity and clean water.

Initially, authorities said only 64 people had died as a result of the hurricane, though that figure only included direct deaths that occurred when the storm hit Puerto Rico.

The GWU study denounces security and health agencies for not having assumed the responsibility of certifying the number of deaths caused by the storm.

The island's governor, Ricardo Rossello, responded to Trump by saying that the people of Puerto Rico do not "deserve their pain to be questioned."

In a video posted on Facebook, Rossello said that the deaths caused by the hurricane should not be exploited for political reasons.

"It's not a time to fight, for political noise, nor to use these things for the benefit of one party or another. It is time to remember those who lost their lives and to acknowledge the pain of their family members," the governor said.

Trump's statement comes just as the southeastern U.S. is preparing for Hurricane Florence, which is expected to hit the coasts of North and South Carolina on Thursday night and Friday morning, threatening to create dangerous flooding in low-lying areas.