DAVIS, Calif. — An American researcher killed in a rock attack by protesters in Ethiopia this week was a talented scientist with a bright future, family members and mentors said Thursday.

Sharon Gray, 31, was a leader in the study of how climate change affects plants, said Savithramma Dinesh-Kumar, chairman of Gray’s plant biology department at the University of California, Davis.

“She’s really an always-smiling slip of sunshine. She’s a smart, energetic scientist,” Dinesh-Kumar said. “She had a very bright future ahead of her. And everyone knew she was going to be the star in the plant biology research area.”

Gray, a post-doctoral researcher, was in the East African country for a meeting to kick off a research project when she was killed Tuesday. She was traveling in a car in the outskirts of the capital, Addis Ababa, an area that has seen months of deadly protests.

A family statement said Gray was “such a bright human being.”

“Sharon was a passionate scientist, friend, spouse, sister, daughter, aunt, godmother, and a colleague,” the statement said. “We are picking each other up and growing together in her absence.”

The family has started a fundraising webpage aimed at mentoring young women in science in her name.

Gray is the first foreigner killed in the massive anti-government protests that have claimed the lives of hundreds of protesters since November 2015. At least 55 were killed in a stampede last weekend when police tried to disrupt a demonstration amid a massive religious festival that has been followed by clashes between security forces and protesters.

The circumstances of the attack that killed Gray are still unclear, Dinesh-Kumar said. Another UC Davis professor who was in Ethiopia was shaken but not hurt and is returning home, he said.

The U.S. Embassy on Wednesday attributed the death to head injuries from a rock thrown by “unknown individuals.”

Gray earned her doctorate at the University of Illinois, Urbana-Champaign in 2013 before moving to UC Davis with her husband, who is also a post-doctoral researcher. She was recently awarded a three-year National Science Foundation grant to study how growing levels of carbon dioxide affect plants.

She traveled to Ethiopia for her first meeting to discuss a separate research project she planned to conduct with the Netherlands Institute of Ecology and charitable organizations.

The U.S. State Department is assisting Gray’s family, said UC Davis Interim Provost Ken Burtis and Mark Winey, dean of the College of Biological Sciences, in a message to the campus community.

“On behalf of the entire UC Davis campus, our hearts and condolences go out to Sharon’s husband and extended family,” they wrote. “Even in tragedy, we hope that we all can find some comfort in the wonderful work Sharon was engaged in that will better the lives of so many around the world.”

This story has been corrected to show that Gray is 31, not 30.