Hazardous materials teams yesterday were investigating several rusty cylinders dug up by construction crews near the site of a shuttered Navy weapons laboratory in the White Oak area of Silver Spring.

The cylinders were unearthed earlier this week. A construction worker called 911 yesterday when he saw at least one of them emitting a gaseous substance, said Montgomery County fire spokesman Pete Piringer.

Officials had not determined what type of gas the cylinders contained, Piringer said. They were found in a remote area of the White Oak Federal Research Center and did not appear to pose a danger to anyone, he said.

Nobody was injured, there were no occupied buildings near the cylinders, and nobody was evacuated from the nearest occupied building, about one mile away, he said.

Piringer said the cylinders do not appear to be weapons. It is possible that heat and sunlight caused the gas in the cylinders to expand after they were dug up, causing the leak.

At least one continued leaking gas through much of the day yesterday. The gas was both visible and audible, Piringer said. Montgomery County hazardous materials crews stood by, waiting for Navy experts to arrive and analyze and dispose of the materials, authorities said.

The 660-acre research center, which spans the Montgomery-Prince George's border, was home to the Naval Ordnance Laboratory, established in 1944. Later called the Naval Surface Warfare Center, the lab developed and tested surface and underwater naval weapons. It was closed in the fall of 1997, said Virginia Bueno, spokeswoman for the Naval Facilities Engineering Command.

The General Services Administration that year took over about 660 acres of the site and is supervising a major construction project for the Food and Drug Administration, which expects to have about 3 million square feet of office space built or renovated in the area by 2011, a GSA spokesman said. The FDA's headquarters will be at the site, on New Hampshire Avenue between Powder Mills Road and Lockwood Drive.