Nearly 5,000 died in Puerto Rico in Maria's aftermath, study says

A study by Harvard University researchers finds that the death count from Hurricane Maria in Puerto Rico is far greater than the official number of 64.

The study, published in the New England Journal of Medicine, finds at least 4,645 people were killed when the vicious storm ravaged the island in the Caribbean in September 2017. That number could increase, the study adds.

"Our results indicate that the official death count of 64 is a substantial underestimate of the true burden of mortality after Hurricane Maria," according to the researchers.

"Our estimate of 4645 excess deaths from September 20 through December 31, 2017, is likely to be conservative since subsequent adjustments for survivor bias and household-size distributions increase this estimate to more than 5000. "

Hurricane Maria blew ashore near the southeast coastal town of Yabucoa as a Category 4 storm with winds of 155 mph (250 kph). It compounded the damage done by Hurricane Irma two weeks earlier.

It was the third-strongest storm to make landfall in the U.S.