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Emergency crews plucked motorists from cars stranded by high water along a seven-mile stretch of south Louisiana interstate, pulled others from inundated homes and waist-deep waters and braced for more of the dangerous work Sunday after conducting at least 2,000 rescues.

Pounding rains swamped parts of southeast Louisiana so that whole subdivisions and shopping centers appeared isolated by floodwaters, which have claimed at least three lives.

Louisiana Gov. John Bel Edwards declared a state of emergency, calling the floods "unprecedented" and "historic." He and his family were even forced to leave the Governor's Mansion when chest-high water filled the basement and electricity was shut off.

"That's never happened before," said the governor, whose family relocated to a state police facility in the Baton Rouge area.

The governor toured flood-ravaged areas by helicopter later Saturday after rivers and creeks burst their banks and warned Louisiana residents it would be too risky to venture out even after the rains start to subside.

In addition to the three confirmed deaths, Edwards said, at least one person is missing.

One of the worries, the governor said, is that as the rain lessens in the next several hours, people will become complacent and feel too at ease in areas where waters may still be rising for several days, getting in cars in areas that could still be dangerous.

"I'm still asking people to be patient. Don't get out and sightsee," Edwards said. "Even when the weather is better, it's not safe."

In one dramatic rescue Saturday, two men on a boat pulled a woman from a car almost completely underwater, according to video by WAFB. The woman, who's not initially visible on camera, yells from inside the car: "Oh my god, I'm drowning."

One of the rescuers, David Phung, jumps into the brown water and pulls the woman to safety. She pleads with Phung to get her dog, but he can't find it. After several seconds, Phung takes a deep breath, goes underwater and resurfaces -- with the small dog. Both the woman and dog appeared OK.

Elsewhere, rescues continued late Saturday, including missions by crews in high-water vehicles who pulled motorists from one swamped stretch of Interstate 12 between Baton Rouge and nearby Tangipahoa Parish.  Maj. Doug Cain, spokesman of the Louisiana State Police, said about 125 vehicles became stranded on the seven-mile stretch, prompting those rescues.

During an aerial tour, an Associated Press reporter saw homes in parts of rural Tangipahoa Parish that looked like little islands among flooded fields. Farmland was covered and streets descended into impassable pools of water.

In the Livingston Parish city of Denham Springs, a suburb of Baton Rouge, entire shopping centers were inundated, only roofs of cars peeking above the water. And in many places, the water was still rising, with days expected before rivers were expected to crest.

Though the governor's office said Saturday that more than 1,000 people had been rescued, that number appeared to at least double by the end of the day, when Livingston Parish Sheriff Jason Ard said 2,000 people in his parish alone had been rescued, and more people still await help.

"We haven't been rescuing people. We've been rescuing subdivisions," he said. "It has not stopped at all today."

In Baker, just north of Baton Rouge, residents were rescued by boats or waded through waist-deep, water to reach dry ground. Dozens of them awoke Saturday morning on cots at a makeshift Red Cross shelter only a few blocks from their flooded homes and cars.

Shanita Angrum, 32, said she called 911 on Friday morning when she realized flood waters had trapped her family in their home. A police officer carried her 6-year-old daughter, Khoie, on his back while she and her husband waded behind them for what "felt like forever."

"Snakes were everywhere," she said. "The whole time I was just praying for God to make sure me and my family were OK."

Beginning Friday, 6 to 10 inches of rain fell on parts of Louisiana and several more inches of rain fell on Saturday, according to the National Weather Service. Some areas got even more rain. In a 24-hour period, Baton Rouge had as much as 11 inches while one weather observer reported more than 17 inches in Livingston.

Forecasters expected a turn to the north Sunday by the system, warning portions of central and northern Louisiana could see heavy rain into next week.

Mississippi Gov. Phil Bryant declared a state of emergency for several counties in his state as it also battled the heavy rainfall.

Meanwhile, the body of a woman from Amite was recovered Saturday from the Tickfaw River, according to Michael Martin, chief of operations for the St. Helena Sheriff's Office.

The woman, her husband and the woman's mother-in-law were driving on a state highway Friday when their car was swept off the road. The woman's husband and mother-in-law clung to a tree for hours before being rescued Saturday, Martin added.

A 68-year-old man died Friday after slipping into a flooded ditch near the city of Zachary, and the body of a 54-year-old man was found in St. Helena Parish, where crews pulled him from a submerged pickup on Louisiana Highway 10, authorities said.

Numerous rivers in southeast Louisiana and southern Mississippi overflowed with officials still uncertain just how widespread the damage would be.

As floodwaters swallowed Lyn Gibson's two-story home in Louisiana's Tangipahoa Parish, she hacked away on a hole near the roof, desperately trying to get to safety. She used a saw, a screwdriver and her feet, knocking her way through wood, vinyl and sheet rock.

"I just kept picking and hitting and prying until I could get a hole big enough," the slightly-built, 115-pound woman said. "I would saw for a while. I'd kick at it for a while."

Eventually, Gibson made it out along with her dogs, to be rescued by National Guard soldiers on a boat.