(CNN) Between 4500 and 2500 BC, the bodies of a couple, believed to be married, were placed carefully side by side in an ancient burial site of the Harappans, one of the world's earliest civilizations.

Thousands of years later, in 2013, a team of Indian and South Korean researchers began excavation work in the necropolis now located in Rakhigarhi -- around 100 miles northwest of India's capital, New Delhi -- in a bid to extract DNA from the skeletal remains.

They discovered dozens of skeletons during the excavation process, which ended three years later. Their finds included the couple, the scientists said in a study published in the peer-reviewed ACB Journal of Anatomy . They believe this is the first Harappan pair confirmed to have been buried together.

"Observation revealed that they died at the same time and they were buried at the same time," said Vasant Shinde, the archeologist who led the team.

The skull of the man was found facing the body of his female partner. "They were intimately placed in the burial," Shinde said. "So we thought maybe they shared [a] very intimate relationship" and were probably husband and wife.

Read More