A fire broke out in the second floor storage area of a downtown department store yesterday, interrupting Christmas shopping for dozens of shoppers and creating havoc for merchants who expected heavy business.

"It's ruined my day," said Ron Campbell as he watched firemen battle the blaze above the Bargaintown department store at 421 Seventh St. NW.

Campbell, manager of the Kinney shoe store across from Bargaintown, said, "Today was going to be a busy day. I had about 20 customers in here until the show started."

The show was a four-alarm fire that sent flames licking through second floor windows above the department store, about a block from the Hecht Co. Billowing smoke could be seen blocks away.

"The glass was coming out of the windows and spraying the crowd on the street," said Phil Ogilvie, who came outside of a building across the street when he heard what he said sounded like "an explosion. Lots of people were screaming and scattering."

The fire began at 11:23 a.m. and within minutes more than 20 fire engines, trucks and ambulances had arrived on the scene. Police quickly cordoned off the area, moving hundreds of shoppers behind ropes about a block away.

Thomas Fitzpatrick was on his way to buy a suit and overcoat from George's Big and Tall Men's Shop, two doors away from the fire, when he and his wife, Evelyn, found they couldn't go beyond the barricade.

"I guess we'll have to come back some other time," Mrs. Fitzpatrick said, "That's a big fire. I doubt if it will be over soon."

Linda Hill, a 24-year-old Northwest Washington woman, had taken the subway downtown to do some shopping at Bargaintown.

"I just got here about five minutes ago," she said as she stretched to see what was going on. When told that there had been a fire above the store where she was planning to stop, she said, "What a shame. There go my baby's presents."

Hill, said she had planned to buy her 6-month-old daughter a doll baby, some overalls, gloves and a snowsuit at Bargaintown.

She said she planned to return downtown next week and "go to Hecht and get what I can get."

But some shoppers waited patiently for the firemen to put out the fire. After about three hours, police finally allowed shoppers along one side of Seventh Street between D and E Streets.

Deborah Barrett, who had waited for two hours with her two children, immediately went to the Kinney's shoe store.

"I thought about going back home, but I didn't want to have to come back down here tomorrow," said Barrett, who lives in Southeast Washington.

She and her two children, Sapriece and William, caught the bus downtown to go shopping for shoes. Barrett bought her son a pair of $10 shoes from the Kinney shoe store.

But she said she would probably still have to return downtown on Sunday because the shoe store where she had planned to buy her daughter's shoes closed because of the fire.

Fire officials said three firemen were slightly injured. They were taken to the Washington Hospital Center, treated, and later released.

Officials said the fire started in a bundle of imitation flowers in a corner of the second floor storage area of the Bargaintown store. The exact cause of the blaze is unknown.

Two store employes tried unsuccessfully to put out the fire with fire extinquishers. The blaze quickly spread to the mattresses, foam rubber, and Venetian blinds on the second floor.

The extent of damage to the building was undetermined late yesterday.