MANVEL, Texas – A 5-year-old boy and his grandmother were killed Monday afternoon when an empty school bus crashed into their car in Brazoria County.

The incident was reported at about 3:19 p.m. at the intersection of Highway 6 and County Road 99 in Manvel and investigators believe speed was a factor.

According to Texas Department of Public Safety Lt. Stephen Woodard, a family in a black sedan was stopped at the red light in the right lane heading West bound when an Alvin Independent School District school bus rear-ended the sedan.

“I helped more with the woman, I tried to keep her alive,” explained Laurent Bray who is a nurse.

Her car was in front of the black sedan. She got out of the car along with others, to help the family of three.

"Praying, telling her I was there and I wasn't going to leave her,” said Bray as she tried to help the 60-year-old grandmother.

Woodard said Karen Sanchez, 60, died from her injures and so did her 5-year-old grandson, who was a Pre-K student from E.C. Mason Elementary School.

“I'm devastated. I'm still in shock so I ask that people please pray for this dear precious family,” said Bray who was at the scene the entire time. “Such a hard loss to take especially at such a young age."

DPS said Sanchez’ husband, 63, was also in the car and was taken to the hospital in stable condition.

Alvin ISD said only the driver was aboard the bus at the time of the crash. The district said the bus was beginning its afternoon route at the time of the incident.

[WATCH: Sky 2 aerials of Alvin ISD school bus accident]

Deputies said Life Flight was called to the scene and the grandchild and grandmother in the black sedan were taken to the hospital via helicopter. Several other vehicles were involved in the crash. A man driving a truck who was involved in the crash was taken to the hospital as well, so was a woman in a red SUV.

Officials said the bus driver is being tested for intoxication and was answering questions.

[DPS gives latest details on fatal bus involved accident]

It is unknown what caused the bus to crash into the family's sedan, but deputies believe speed could be a factor.

All lanes on Highway 6 were shut down.

Alvin ISD released the following statement:

“Our hearts and minds are grieving right now for the members of the family involved in this unthinkable tragedy. This tragedy is too difficult to process and the emotions are too raw to feel anything but hurt and sadness for the family. This family is at the forefront of our minds at this time.

“As a community, we ask you to wrap your love and support around the family. This tragedy impacts our community as a whole, including those at E.C. Mason Elementary that cared deeply for our student and his family.

“The Alvin ISD Crisis Response Counselors will be at E.C. Mason Elementary to offer assistance for those that are grieving this unthinkable loss. Crisis Counselors will remain on campus to offer their support to students and staff members as long as they are needed.

“Alvin ISD will fully comply and assist all law enforcement agencies as they conduct their investigation. The Texas Department of Public Safety is currently leading the investigation. The driver of the bus has fully complied with the investigation including willfully submitting to a toxicology screening.

Please continue to keep the family in your thoughts and prayer.”

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