The two Americans killed during an ISIS-claimed terror attack in Tajikistan were Washington, D.C.- area cyclists with a mission to bike across the globe.

Lauren Geoghegan and Jay Austin were among the four foreigners killed when a car rammed into their group south of the Tajik capital of Dushanbe on Sunday. The other victims were from Switzerland and the Netherlands.

Officials said the terrorists rammed into the group in Khatlon Oblast before getting out and attacking them with knives. ISIS claimed responsibility for the attack, while Tajik officials have pointed to another extremist group in the country.

According to their blog, Geoghegan and Austin began their journey in July 2017 in South Africa. They made their way to Dar es Salam then to Europe. In May, they flew from Istanbul, Turkey to Almaty, the largest city in Kazakhstan.

They last blog post was from July 11 after they cycled from Too Ashuu to Ala-Bel in Kyrgyzstan.

“We coast into a gorgeous green valley. We freewheel past yurts and cows and little Kyrgyz kids and their enthusiastic waves,” Austin wrote. “We pass a French cyclist coming in the other direction, stop to compare notes on roads cycles, and ride on just a little longer.”

Geoghengan’s family released a statement on Tuesday, saying the couple’s yearlong bicycle adventure “was typical of her enthusiastic embrace of life’s opportunities, her openness to new people and places, and her quest for a better understanding of the world.”

“Lauren’s sisters are deeply saddened by the loss of their older sister but treasure their rich memories of her love and of the example she set for them,” the statement continued, according to FOX5 DC. “We want to thank the staff of the U.S. Embassy in Dushanbe, Tajikistan, for their capable and compassionate assistance to our family at this difficult time.”

Georghegan was a 29-year-old graduate of Georgetown University, where she majored in government and minored in Spanish and Arabic. She worked at the university’s admissions office.

“We are heartbroken to hear of Lauren's passing in this devastating tragedy and have expressed our deepest condolences to her family. Lauren was a valued colleague and dear friend to many at Georgetown and an overall treasured member of our community,” Georgetown University Dean of Admissions Charles Deacon said in a statement.

Austin worked at Boneyard Studios, a small company building sustainable homes.

“The tiny house world just lost a beautiful soul. Jay Austin, of the former Boneyard Studios, left this world doing what he loved (connecting with people and cycling the world) with the person he loved (Lauren Geoghegan),” the company said in a Facebook statement. “Jay, you didn't only build a house, you built a home for yourself and for so many around you. Thank you for all the beauty and light you brought into this world.”

The U.S. State Department said it is working closely with Tajik authorities to investigate the attack.