Prince George's County health officials said yesterday that at least 62 persons who ate at the Forestville Volunteer Fire Department last weekend became ill with salmonella poisoning, bringing to more than 300 the number of suspected cases involved there and in an earlier outbreak at an Oxon Hill steak house.

While officials have been unable to determine the source of either outbreak, they have found that the same food distributor served the firehouse and the Ranch House Restaurant in Oxon Hill, said Dr. Helen B. McAllister, county health officer.

McAllister cautioned, however, that the link may mean nothing. She said investigators also are checking other factors that may have led to the salmonella, a bacterium that infects the gastrointestinal tract and is often found in undercooked or improperly stored food.

At both the firehouse and the restaurant, meats were not stored at cool enough temperatures, she said. In addition, investigators are concerned about food-handling practices at the restaurant, which health officials closed Monday night after 31 cases of food poisoning came to light.

"For example, a whole ladle might be left in the coleslaw so it meant reaching in with the hands to pull it out," McAllister said in a news conference yesterday.

Of the original 31 cases stemming from the restaurant, 13 persons have been hospitalized, she said. Only one of the diners at the fire department's weekend fund-raiser required hospitalization.

Since the outbreak was reported Monday, about 300 other Ranch House patrons have telephoned the health department to report illness after eating there, McAllister said.

Two restaurant employes have also been ill, she said, but it is impossible to tell at this point if they were the source of the poisoning or just ate infected food there.

In all of the confirmed cases, she said, diners had eaten at the Ranch House on May 30 or May 31, but several of the callers have mentioned dining there several days earlier.

The symptoms of salmonella, which usually occur within 72 hours of eating infected foods, include sudden cramps, diarrhea, fever, headaches and vomiting. It is rarely fatal, but can be dangerous to children, the elderly or people with weak immune systems. As many as 3 million cases are reported in the United States annually.