ERIE, Pa. -- State and federal environmental officials are trying to determine the cause of a big stink reported along Lake Erie.

Hundreds of residents called authorities or the National Weather Service yesterday to report the smell, which has been variously described as like gasoline, natural gas or even decaying garbage and rotten eggs. The smell was strongest yesterday morning when a cold front swept through the area, churning up larger than normal waves from Erie to Dunkirk, N.Y., officials said.

Scientists said tests run so far aren't conclusive, but they believe the churning waters may have released some naturally occurring gases that are normally trapped beneath the lake's deeper waters. Decaying plants and fish washed ashore by the waves could also be contributing to the stench.

Pennsylvania Department of Environmental Protection biologist Jim Grazio said the wave-churning theory makes sense because the smell lessened when the waves diminished.

"It's like the lake burped, and then the burp passed by us," Grazio said.