Nelson Soto Sr. and wife Elvia Hercules

Chastity Thornell, 21, was killed in an early morning apparent hit and run Wednesday, May 30, 2012

Nelzon Soto Sr. and wife Elvia Hercules

KNOXVILLE, Tenn. (WVLT) -- Knoxville police now know who was behind the wheel of the SUV that killed Chasity Thornell, her unborn child and Nelson Soto early this morning.

They're not releasing his identity until they make an arrest. Police say he already has a lawyer.

They also found the white 2004 Ford Explorer around 2:00 Wednesday afternoon. Once investigators process the SUV, they will seek warrants for his arrest.

Chasity Thornell, who police said was about seven months pregnant. The baby did not survive either.

According to police, Thornell and another woman ran out of gas in front of Soto's home in the 2400 block of Washington Pike shortly before 2:00 a.m. After he finished adding gas to their car, the women hugged him to say thanks.

That's when police say a Ford appeared, traveling at a high rate of speed and hit Soto and Thornell, who were pronounced dead at the scene. The other woman was not hit.