The Puerto Rican government has sharply raised the death toll from Hurricane Maria on the island last year to 1,427, about 20 times more than the previous official count.

In a draft report to Congress posted online Thursday, the government said the number of deaths was revised based on public health records.

"Although the official death count from the Puerto Rico Department of Public Safety was initially 64, the toll appears to be much higher," the report said.

It also said 527,000 homeowners reported damage to their homes and about 40 schools permanently closed because of structural damage caused by the storm in Puerto Rico, an unincorporated territory of the United States located in the northeast Caribbean Sea, with a population of 3.4 million.

Pedro Cerame, a spokesman for the Puerto Rican Federal Affairs Administration, told The New York Times that the latest death toll figure is unofficial, but is a "realistic estimate."

"The official number will come, and it could be close. But until we see the study, and have the accuracy, we won't be able to recognize the number as official," said the spokesman.

The study the spokesman was referring to was carried out by George Washington University and was commissioned earlier this year to examine the death toll.

The Puerto Rican and the U.S. federal governments have come under scrutiny over the accounting of the deaths caused by the storm, which struck the island as a Category 4 hurricane in September 2017 and caused widespread destruction and plunged it into a months-long blackout.

The death toll is a contentious topic, in part because federal and island governments haven't responded as rapidly to the disaster as they have in other hurricane emergencies.

Perhaps about 5,000 people died in Puerto Rico as a result of Hurricane Maria in 2017, according to another study published in May by scientists at the Harvard T.H. Chan School of Public Health.

The U.S. federal government has been heavily criticized for its response to the storm and the island's recovery efforts.