A spokeswoman for ConAgra, Julie DeYoung, said at Saturday's news conference that the company would not comment on its security procedures or how the guns got into the plant, nor would she say whether there were any disciplinary or grievance issues involving Mr. Brown. She said he had been hired last September as a manufacturing line worker, laid off earlier this year because of a production slowdown and rehired six weeks ago.  The police also were not sure whether it was coincidence or not that three of the dead men were related. Lonnie Ellenberg, 46, and Travis Nelson, 23, both of Kansas City, and Mr. Edwards, the man who died early Saturday, were all part of an extended family, said Col. Sam Breshears, a deputy police chief.  Colonel Breshears said one of the dead men was a Mexican citizen whose name would not be released until his family could be located. He identified the other victim as Leonardo Rodriquez, 49, also of Kansas City. Two other wounded men are expected to survive, Colonel Breshears said.  People who work in the meatpacking industry here and in the auxiliary niche businesses that serve the industry, from warehousing to refrigerated shipping, said the environment of a meat factory is probably an important element in explaining what happened at the plant. The work is high-speed and high-pressure, they said, which often means a person cannot spare too much attention noticing whether a co-worker who is acting suspiciously or not. Lose focus, the workers said, and you risk getting behind on the line.  ''It's a very stressful environment,'' said Eleazar DeLeon, 39, who left meat manufacturing after a few years and now works for a meat shipping and distribution company. Mr. DeLeon works nights at his job and had stopped for breakfast after work at a diner around the corner from the ConAgra plant. ''Any processing plant is repetitive line work,'' he added. ''It's very hard.''  Employees at ConAgra said the bulky coats that everyone wears, both for warmth in the 40-degree refrigerator chill of the factory and for identification -- production side workers at ConAgra wear blue coats, packaging side workers wear white -- would also make it easy to conceal a weapon once it was on the factory floor. Many people also carry lunch boxes and coolers into the plant that have not routinely been searched in the past, one employee said.  Edna Perkins is a career meat-processing worker, with 28 years on the line. She was one of the 160 or so people at the plant on Friday, and was also related to Mr. Ellenberg, Mr. Nelson and Mr. Edwards, though she described the men as being from ''another side of the family.''  Just after 5 p.m., Mrs. Perkins said, she was at her job as usual -- she's a white-coated ''boxer'' on the packaging side, assigned the task of packing prepared meat for shipping -- when she saw people running above her on the catwalk that extends out over the production floor. A few seconds later a man walked by above her, bleeding.  ''My first thought was that they'd had a mechanical accident,'' she said. Then everyone started running and next thing she knew she was outside the plant in the parking lot. Interviewed by telephone Saturday morning from her home, Mrs. Perkins said she had been unable to sleep all night.  On Saturday, the plant was closed, sealed by police barricades on the driveway, and the ConAgra spokeswoman, Ms. DeYoung, said she did not know yet when it would reopen. Counseling sessions were being offered on Saturday for employees.  The shooting followed by a year and a day an attack in which a manufacturing plant employee in Jefferson City, Mo., killed three people and then himself.  Meat industry work has deep roots in Kansas City, where a nexus of railroads and ranching combined to build a culture of stockyards and packing plants beginning in the late 1800's.  The industry has declined significantly over the last 50 years, but remains alive in the neighborhoods like Amourdale, named for the meat company, and in factories like ConAgra. In recent years, workers here say, the plants have also increasingly become the province of immigrants from Mexico and other Latin American countries.  Even on Saturday as the ConAgra plant sat silent and employees mourned, the city's culture of heavy trucking, rail and agriculture continued. As Chief Miller and other officials spoke at the news conference, reporters repeatedly had to lean in to hear, the speakers forced to shout, as another tractor-trailer rumbled by the factory door.
Elijah Brown goes on shooting rampage at ConAgra Foods meatpacking plant in Kansas City, Mo, killing five co-workers before shooting himself; sixth victim dies later; two wounded men are expected to live; motives are unclear, but victims seem to have been deliberately chosen; one witness talks about confrontation between Brown and co-worker earlier in week; workers suggest stress of high-speed, high-pressure work at plant may have played role; photo (M)