SAN ISIDRO, PUERTO RICO - OCTOBER 15:  Uncollected debris stand near damaged homes in an area without electricity on October 15, 2017 in San Isidro, Puerto Rico. Puerto Rico is suffering shortages of food and water in many areas and only 15 percent of grid electricity has been restored. Puerto Rico experienced widespread damage including most of the electrical, gas and water grid as well as agriculture after Hurricane Maria, a category 4 hurricane, swept through.  (Photo by Mario Tama/Getty Images)
PHOTO: Mario Tama/Getty Images South America/Getty Images
SAN ISIDRO, PUERTO RICO - OCTOBER 15: Uncollected debris stand near damaged homes in an area without electricity on October 15, 2017 in San Isidro, Puerto Rico. Puerto Rico is suffering shortages of food and water in many areas and only 15 percent of grid electricity has been restored. Puerto Rico experienced widespread damage including most of the electrical, gas and water grid as well as agriculture after Hurricane Maria, a category 4 hurricane, swept through. (Photo by Mario Tama/Getty Images)
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SAN ISIDRO, PUERTO RICO - OCTOBER 15:  Uncollected debris stand near damaged homes in an area without electricity on October 15, 2017 in San Isidro, Puerto Rico. Puerto Rico is suffering shortages of food and water in many areas and only 15 percent of grid electricity has been restored. Puerto Rico experienced widespread damage including most of the electrical, gas and water grid as well as agriculture after Hurricane Maria, a category 4 hurricane, swept through.  (Photo by Mario Tama/Getty Images)
PHOTO: Mario Tama/Getty Images South America/Getty Images
SAN ISIDRO, PUERTO RICO - OCTOBER 15: Uncollected debris stand near damaged homes in an area without electricity on October 15, 2017 in San Isidro, Puerto Rico. Puerto Rico is suffering shortages of food and water in many areas and only 15 percent of grid electricity has been restored. Puerto Rico experienced widespread damage including most of the electrical, gas and water grid as well as agriculture after Hurricane Maria, a category 4 hurricane, swept through. (Photo by Mario Tama/Getty Images)
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MOROVIS, PUERTO RICO - DECEMBER 20:  A resident, whose home remains without electricity, watches as debris is removed on December 20, 2017 in Morovis, Puerto Rico. Barely three months after Hurricane Maria made landfall, approximately one-third of the devastated island is still without electricity and 14 percent lack running water. While the official death toll from the massive storm remains at 64, The New York Times recently reported the actual toll for the storm and its aftermath likely stands at more than 1,000. Puerto Rico's governor has ordered a review and recount as the holiday season approaches.  (Photo by Mario Tama/Getty Images)
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MOROVIS, PUERTO RICO - DECEMBER 20: A resident, whose home remains without electricity, watches as debris is removed on December 20, 2017 in Morovis, Puerto Rico. Barely three months after Hurricane Maria made landfall, approximately one-third of the devastated island is still without electricity and 14 percent lack running water. While the official death toll from the massive storm remains at 64, The New York Times recently reported the actual toll for the storm and its aftermath likely stands at more than 1,000. Puerto Rico's governor has ordered a review and recount as the holiday season approaches. (Photo by Mario Tama/Getty Images)
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SAN JUAN, PUERTO RICO - SEPTEMBER 30:  San Juan Mayor Carmen Yulin Cruz speaks to the media as she arrives at the temporary government center setup at the Roberto Clemente stadium in the aftermath of Hurricane Maria on September 30, 2017 in San Juan, Puerto Rico.  Puerto Rico experienced widespread damage including most of the electrical, gas and water grid as well as agriculture after Hurricane Maria, a category 4 hurricane, passed through.  (Photo by Joe Raedle/Getty Images)
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SAN JUAN, PUERTO RICO - SEPTEMBER 30: San Juan Mayor Carmen Yulin Cruz speaks to the media as she arrives at the temporary government center setup at the Roberto Clemente stadium in the aftermath of Hurricane Maria on September 30, 2017 in San Juan, Puerto Rico. Puerto Rico experienced widespread damage including most of the electrical, gas and water grid as well as agriculture after Hurricane Maria, a category 4 hurricane, passed through. (Photo by Joe Raedle/Getty Images)
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Residents of San Juan, Puerto Rico, deal with damages to their homes on September 20, 2017, as Hurricane Maria batters the island. 
Maria slammed into Puerto Rico on Wednesday, cutting power on most of the US territory as terrified residents hunkered down in the face of the island's worst storm in living memory. After leaving a deadly trail of destruction on a string of smaller Caribbean islands, Maria made landfall on Puerto Rico's southeast coast around daybreak, packing winds of around 150mph (240kph).
 / AFP PHOTO / HECTOR RETAMAL        (Photo credit should read HECTOR RETAMAL/AFP/Getty Images)
PHOTO: HECTOR RETAMAL/AFP/Getty Images
Residents of San Juan, Puerto Rico, deal with damages to their homes on September 20, 2017, as Hurricane Maria batters the island. Maria slammed into Puerto Rico on Wednesday, cutting power on most of the US territory as terrified residents hunkered down in the face of the island's worst storm in living memory. After leaving a deadly trail of destruction on a string of smaller Caribbean islands, Maria made landfall on Puerto Rico's southeast coast around daybreak, packing winds of around 150mph (240kph). / AFP PHOTO / HECTOR RETAMAL (Photo credit should read HECTOR RETAMAL/AFP/Getty Images)
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Hurricane Maria pummels Puerto Rico
(CNN) —  

Puerto Rico’s new death toll from Hurricane Maria is making the storm one of the deadliest hurricanes in US history.

Authorities raised the death toll from last year’s storm to 2,975 on Tuesday, which surpasses that of both Hurricane Katrina in 2005, which is responsible for 1,833 deaths, and the 1928 Okeechobee hurricane in Florida, which killed 2,500 people.

The count in Puerto Rico could change as the government continues to investigate deaths from the storm, Puerto Rico Gov. Ricardo Roselló said. Until the recent update, Puerto Rico’s government had said only 64 people died as a result of the storm.

The Great Galveston Hurricane of 1900 remains the deadliest recorded hurricane in US history.

Thousands of homes in the city of Galveston, Texas were reduced to rubble by a hurricane on Sept. 8, 1900.
PHOTO: Library of Congress
Thousands of homes in the city of Galveston, Texas were reduced to rubble by a hurricane on Sept. 8, 1900.

When it made landfall on September 8, 1900, it destroyed thousands of homes and killed at least 8,000 people within hours. The hurricane hit the Texas port city by surprise and had such a massive impact that it “brought a new focus on the study of hurricane prediction,” the National Oceanic and Atmospheric Administration said.

All three of the deadliest hurricanes were Category 4 storms when they made landfall.

Deadly estimates in the spotlight

News organizations and some members of Congress have raised questions about the official death toll in Puerto Rico, which had remained at 64 for months.

CNN reporters surveyed about half of the funeral homes across the island and found that funeral home directors identified 499 deaths they considered to be hurricane-related. In December, The New York Times estimated 1,052 “excess deaths” occurred after Maria. Others produced similar estimates.

Democrats in the House, including some Hispanic Caucus members, have requested an investigation into the Trump administration’s response to Hurricane Maria.

In June, Democratic Rep. Nydia Velázquez called for a commission similar to one established in the aftermath of 9/11 to look into the storm’s “death toll, the federal response and how FEMA and other agencies may have responded sluggishly based on artificially low numbers.”

CNN’s Leyla Santiago, Catherine E. Shoichet and Jason Kravarik contributed to this report.