Image copyright KOAT Albuquerque Image caption Jacob and Ursula Kokotkiewicz were found in their vehicle on Thursday

Police have identified a married couple discovered shot dead inside a pick-up truck parked along a highway in the US state of New Mexico.

Jacob and Ursula Kokotkiewicz, of Texas, were found on Thursday by police who went to investigate a vehicle parked on the side of the road.

Police say both had been shot in the head and the man had a handgun between his legs.

Investigators are trying to determine a motive.

Mrs Kokotkiewicz, 32, who was discovered in the front passenger seat of the vehicle, was a teacher in Dallas.

Image copyright Family handout Image caption Mrs Kokotkiewicz was a teacher in Dallas

She had studied education and literature at the University of Toronto, according to her Facebook page.

Mrs Kokotkiewicz and her 31-year-old husband had been visiting National Parks, according to her Instagram feed.

In a recent post from Utah, she uploaded a photo with a comment: "To me, the journey matters as much as the destination. Savor the moments and enjoy life's detours."

Tributes have been flooding in on Instagram for her.

"I can't believe Ms K is gone," read one comment.

"I should have gotten a picture, a hug or something, and I didn't because I expected to see her again."