A young couple from Northern Virginia were found shot to death in the median of a rural highway hours away from home, relatives say.

Ayanna Maertens-Griffin, 18, and her 21-year-old boyfriend Joel Bianda were found dead early Saturday on an isolated stretch of Route 58 in Halifax County, Virginia State Police said. Their silver Nissan Maxima was nearby.

They both were shot once in the head, relatives told News4.

Maertens-Griffin's father George Maertens Aramayo was supposed to get married this week. Instead, he’s making funeral arrangements for his daughter.

"So many things running through my head. It's, you know, from one extreme to the other. I definitely now understand the words of a parent's true nightmare," Maertens Aramayo told News4 sister station WSLS.

Family members said Bianda told them he and Maertens-Griffin were driving to Danville, Virginia, to pick up a friend.

Maertens-Griffin graduated from Northwest High School in Montgomery County at age 16, her mother told News4. She took computer science classes at Northern Virginia Community College and recently moved to Fairfax County.

"Even through the worst of days, she would light up, you know, anyone's face if they were having a rough day. Beautiful personality. Beautiful human. Everyone that encountered her loved her," her mother, Melissa Griffin, said.

Griffin said she spoke to her daughter Friday night and she had not mentioned any plans to go to Danville.

She said she hopes police will find her daughter's killer quickly.

"I hope that whoever is responsible for this is caught and, you know, punished to the fullest extent," she said.

Bianda's family declined comment, asking for privacy as they grieve.

Editor's Note: Police on Thursday arrested a high school student from Northern Virginia in the killings of Maertens-Griffin and Biana. Read the latest updates.