What we know: Mississippi braces for intense flooding as Pearl River swells

Mississippi Gov. Tate Reeves (R) has declared a state of emergency as authorities brace for "historic" floods, with days of rain expected, as the Pearl River continues to swell in and around the state capital, Jackson.

What's happening: Evacuations have already begun, and the river isn't expected to crest until Monday. Reeves described the situation as precarious. "We expect water to stay in the area for 2-3 days, with rain throughout the week," he tweeted.

• Projections indicate Mississippi could experience the "third-worst flood in our state’s history," Reeves said in a Twitter post announcing the emergency declaration on Saturday.

Evacuations: The Department of Wildlife and Fisheries went door-to-door to alert 510 people "in an effort to evacuate the areas," MEMA said Sunday.

• The Office of Homeland Security assisted in four evacuations in two counties, it added.

The impact: Four injuries have already been reported and 18 counties had submitted damage reports to the Mississippi Emergency Management Agency by Sunday.

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Editor's note: This story will be updated as it develops.