A father of four was shot and killed by police in a case of mistaken identity following an armed robbery in Downey, investigators said Sunday.

The Los Angeles County sheriff's department said Michael Nida, 31, was most likely not the robbery suspect Downey police were searching for following an armed robbery near Imperial Highway and Paramount Boulevard around 7:20 p.m. Saturday.

"Officers were responding to a robbery of a citizen on the street, '' Downey police Sgt. Perry Miller. "When they saw two suspects matching their descriptions, a pursuit started."

Officers contained the area and found Michael Nida, 31, in the yard of a nearby house. Nida tried to flee again but was captured at Imperial Highway and Paramount Boulevard, police said.

Nida escaped detention a third time and led officers on a short foot pursuit. According to police, at one point, Nida turned toward the pursuing officers in an aggressive manner.

Fearing he was armed, an officer fired at Nida, striking him, police said.

Nida was detained and transported to a local hospital, where he was later pronounced dead.

The Los Angeles County sheriff's department said Nida was not armed.

Two suspects are still at large, sheriff's deputies said.

Nida's sister told CBS2 that her brother was just out getting cigarettes.

"My brother and his wife were getting gas. He went across the street to get some cigarettes," Terri Teramura said. "He jaywalked, I guess. And the police saw him. Confronted him. I don't know what happened, but they shot him ... in the back. Five times. Killed him."

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