LUBBOCK, Texas — The Texas Tech University Health Sciences Center and the School of Medicine released a statement Monday regarding the passing of alumni Dr. John Cheng, MD.

Dr. Cheng died Sunday after charging at a shooter who opened fire during a lunch banquet at Geneva Presbyterian Church in Laguna Woods, California. Five others were injured in the shooting, officials said.

“In a moment of crisis, he placed the lives of his neighbors before himself — and by every account, that act of selflessness and courage, which cost him his life, saved the lives of many others,” the statement said. “It was heroism in its purest form.”

Dr. Cheng graduated from the TTUHSC School of Medicine in 1995, according to the statement.

“TTUHSC and the School of Medicine are deeply proud of the legacy he leaves behind,” the statement said.

Read the full statement below:

Texas Tech University Health Sciences Center and the School of Medicine are deeply saddened to learn of the loss of alumnus John Cheng, M.D. We extend our sincerest condolences and prayers to Dr. Cheng’s family, including his wife, and their two children.

Dr. Cheng’s heroic acts in Sunday’s shooting at Geneva Presbyterian Church in California reflected his lifelong dedication to service. In a moment of crisis, he placed the lives of his neighbors before himself—and by every account, that act of selflessness and courage, which cost him his life, saved the lives of many others. It was heroism in its purest form.

Dr. Cheng was a 1995 graduate of the School of Medicine and the proud product of a family of physicians who immigrated to the U.S. from Taiwan. He earned a reputation as an energetic student who was deeply devoted to patient care and carried that same ethic to his practice in Southern California, where he served the community as a beloved family and sports medicine physician. TTUHSC and the School of Medicine are deeply proud of the example and the legacy he leaves behind.