Officer’s Slayers May Be Part of Robbery Ring, Authorities Say : Crime: The suspects might have pulled 30 armed holdups of stores, including one in which a grocer was killed. They are expected to be charged today in the murder of a Maywood patrolman.

Three men arrested in the fatal shooting of a Maywood police officer during the holdup of a neighborhood market may be involved in dozens of other armed robberies, including one in which a grocer was killed, authorities said Monday.

“It appears they’ve been very, very active--extremely active,” said Sheriff’s Lt. Tom Johnston, who is heading the investigation of the killing May 29 of Officer John A. Hoglund.

Johnston said that since Hoglund’s death, his office has been inundated with calls from police departments investigating cases similar to the armed robbery Friday at George’s Market on East 52nd Street in Maywood.

Five men with guns took over the small, Korean-owned liquor and grocery store, methodically searching for money and escaping with as much as $6,000 in cash, Johnston said. On their way out, they encountered and shot Hoglund, who had been called to the store by a silent alarm. The 46-year-old patrol officer--the first Maywood Police officer killed in the line of duty--never had a chance to draw his own gun, investigators said.

Aided by the market’s security video cameras, deputies on Sunday arrested three Los Angeles men--Jose Contreras, 20, Hector Reyna, 21, and Carlos Juarez, 22, the alleged triggerman. Two more alleged accomplices remain at large.

Prosecutors were expected to file charges today against the three arrested men, who were being held without bail.

Although sheriff’s deputies have turned up no evidence of criminal records for the three, Johnston said he believes they are part of a large robbery ring responsible for at least 30 holdups. All the robberies involve family-owned markets or restaurants, although different groups of four or five men may be involved, Johnston said.

One case being compared to the robbery after which Hoglund was killed is the May 4 shooting death of grocer Lee Chul Kim in the San Fernando Valley.

Kim, 49, was killed during a struggle after four armed robbers ransacked the cash registers in his store, the Woodley Market. Police said they believe Kim’s killers are also part of a robbery ring responsible for as many as 20 holdups in the Valley alone.

Police and City Councilman Joel Wachs on Monday announced a $25,000 reward for information leading to the convictions of Kim’s killers.

But authorities said Monday no link between the killings of Hoglund and Kim has been established.

The surveillance tape from the Maywood market was broadcast on television Sunday, however, and witnesses in Paramount have told police that Hoglund’s alleged killers are the same men who victimized them in a recent armed robbery, Johnston said.

Police in South Gate, Bell, Huntington Park and Pasadena are investigating similar robberies, Johnston said.