(CNN) -- The U.S. Fish and Wildlife Service is battling a large grass fire in the marshlands of Jefferson County, Texas, an agency official told CNN on Tuesday.





The fire began Monday afternoon about 12 miles west of Sabine Pass and about 200 yards from the Intracoastal Waterway, Jim Stockie, spokesman for the fish and wildlife service said. He estimated the area burned by Tuesday afternoon to be between 10,000 and 12,000 acres, but he said the fire was not threatening any structures.





Smoke from the blaze was drifting into the Houston/Galveston area more than 100 miles from the fire.





Just a dozen firefighters were working the blaze, Stockie said.





"We don't like to put firefighters out in a sea of grass. We retreat to levies and burn off the fuel," Stockie said.





Texas has suffered its worst fire season in state history with more than 3.5 million acres burned, according to state officials.





In October, the Bastrop Complex Fire torched more than 1,500 homes and 34,000 acres of land north of Austin before officials were able to contain it, the Texas Fire Service said.





An unusual La Nina weather pattern led to a nearly 11-month fire season in the state, fire service spokeswoman April Saginor said.





A survey released last month by the Texas Forest Service estimated between 100 million and 500 million trees, or 2% to 10% of the state's 4.9 billion trees, were killed by the severe drought and consequent fires. The dry spell that began in 2010 was the worst the state has seen since 1895, Texas Lt. Gov. David Dewhurst has said.





The drought conditions also caused concern for the state's water supply, especially in smaller towns.





CNN's Dave Alsup and Chandler Friedman contributed to this report.
How many miles has the smoke drifted When did the fire begin What number of firefighters are working the blaze? How far away has smoke drifted? How many firefighters are working? What did the official say? What day did the fire begin?
100 Monday afternoon a dozen more than 100 miles from the fire. a dozen The Monday afternoon
question: How many miles has the smoke drifted, answer: 100 | question: When did the fire begin, answer: Monday afternoon | question: What number of firefighters are working the blaze?, answer: a dozen | question: How far away has smoke drifted?, answer: more than 100 miles from the fire. | question: How many firefighters are working?, answer: a dozen | question: What did the official say?, answer: The | question: What day did the fire begin?, answer: Monday afternoon