Sept 23 (Reuters) - Four workers were injured on Tuesday in a storage tank fire at a natural gas production facility at top gas producer EOG Resources Inc in Wyoming, the company said.

The EOG employees and two contract workers were cleaning the tank at the time of the fire at about 2 p.m., said Houston-based EOG Resources spokeswoman K Leonard.

"The tank stores natural gas, and was undergoing cleaning when the explosion occurred," the Lincoln County Homeland Security & Emergency Management said in a statement, adding that the fire at the facility south of La Barge is under control.

Leonard, however, said it was a "flash fire": "We would not describe it as an explosion."

Three of the men were taken to hospital for treatment and a fourth was treated and released from an outpatient facility, Leonard said.

Leonard did not immediately respond to questions about the cause of the fire or the extent of damage and disruption to operations.

An April explosion shut down a Williams Companies Inc natural gas-processing plant about 40 miles south of La Barge, in Opal, that was able to churn out about 2 percent of the daily U.S. gas supply, and a nearby town was evacuated.

EOG Resources is one of the largest independent crude oil and natural gas companies in the United States, it says.

(Reporting by Eric M. Johnson; Editing by Robert Birsel)