Story highlights A nurse was killed trying to protect patients, hospital system CEO says

One survivor remains in critical condition

Police say they have a suspect in custody, but don't have a motive

The attack happened at Good Shepherd Ambulatory Surgical Center in Longview, Texas

Gail Sandidge rushed to help when screams rang out during a stabbing at a Texas medical center on Tuesday.

Horrified patients and family members watched as a man stabbed the nurse in the chest.

"She was just saying...'I'm hurt. He got me,'" witness Jana Jackson told CNN affiliate KLTV . "And that's when we realized there was blood all on the front of her scrubs."

Hours later, authorities pronounced Sandidge dead. Police said four others were wounded when 22-year-old suspect Kyron Templeton attacked visitors and employees Tuesday morning at Good Shepherd Ambulatory Surgical Center in Longview, Texas.

The hospital's president told reporters that the dedicated nurse died trying to save her patients.

"Nurses are protectors by nature. And Gail, she fit that profile," said Steve Altmiller, head of Good Shepherd Health Systems. "She was protecting her patients in an act of courage today, and in so doing, she lost her life."

He described Sandidge as "a seamstress, a Sunday-school teacher of 2-year-olds, a huge Baylor fan, a mother, a grandmother, a healer, a trainer, a mentor, a nurturer." She had worked for the hospital for nearly two decades, he said.

Police arrested Templeton on a street near the hospital, KLTV reported. He was arraigned on one count of first-degree murder and four counts of aggravated assault with a deadly weapon Tuesday. But authorities haven't identified a motive, a police spokeswoman said.

Witnesses told KLTV they saw a man running through the surgery center around 7 a.m. with a hunting knife, screaming, "You're not going to kill my mother."

"He had a death grip on the knife and he was just muttering and his eyes were kind of wild-looking," said Jackson's husband, Chad. "It was just, he was very confused."

Moments later, the surgery center about 120 miles east of Dallas turned into a crime scene.

Some staff members rushed patients into safe areas. Others performed CPR on the victims, Chad Jackson told KLTV.

One of the injured victims remained in critical condition Tuesday afternoon, Altmiller said. Another is in good condition. Two others, including a hospital employee, were treated and released, he said.

Templeton is being held on $2.6 million bond as the investigation continues, KLTV reported.

Meanwhile, the Jacksons say they're trying to explain what happened to their two young daughters.

"We're just telling them there's bad people out there," Chad Jackson told KLTV. "There's not a lot of things we can do about the craziness in the world. That's why we go to church. They pray. They say their prayers every night."

And now, he said, Sandidge and her family will be in their prayers.