More search teams and trained dogs were brought in Tuesday as authorities expanded their search for a 2-year-old girl whose family's home was swept away during flooding blamed for at least five deaths.

The girl and her 5-year-old sister, mother and grandmother were all inside the mobile home when it was washed down Pecan Creek early Monday after torrential storms poured nearly a foot of rain on parts of North Texas.

Their mother was rescued, but the bodies of the oldest child and 60-year-old grandmother were recovered from the water, Texas Department of Public Safety Trooper Rebecca Uresti said.

Authorities also were looking for at least four other people Tuesday, searching the creek and checking to see if the four were among the hundreds forced from their homes and staying in two shelters.

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Gov. Rick Perry sent three helicopters and Texas National Guard troops and equipment to help with the searches.

About 500 homes were flooded in and around Gainesville along the Oklahoma state line. At one point, some 450 displaced residents had sought refuge at the shelters.

Among the other victims of the flooding, 4-year-old Alexanderia Collins died after she was swept away in Haltom City, about 60 miles south in the Fort Worth suburb of Haltom City.

A woman died in Sherman, about 35 miles east of Gainesville, after her car stalled in rising water and was swept away, police said. A 74-year-old man died after driving into high water, authorities reported.