A robbery at a Texas shopping mall left one person who tried to intervene dead, three others shot and another two people in hospital.
Police Chief William McManus said two suspects robbed a jewellery store at the Rolling Oaks Mall in San Antonio on Sunday.
"What we have here is a robbery gone really, really bad," he said.
After the suspects fled the store, a man, described by Mr McManus as a "good Samaritan" tried to stop the two men.
One of the robbers then fatally shot the man.
A second individual, who was carrying a licensed concealed weapon, then shot and wounded the robber who had killed the person who intervened, Mr McManus said.
He called the fatal shooting "absolutely senseless".
The victim's name was not immediately released by authorities.
The other robber fled the mall, firing his weapon and injuring a man and a woman. A suspect was arrested later, Mr McManus said.
The injured man and woman, along with the wounded robber, were taken to hospital, said San Antonio Fire Chief Charles Hood.
Two other people- a woman who complained of chest pains and a pregnant woman who had labour pains - were also taken to hospital.
The condition of the people who were injured in the incident was not immediately available.