The woman heard the screen door slam in her upper Northwest Washington house, realized it wasn’t her husband and soon found herself struggling with a daylight burglar.

After a scuffle in the house on Broad Branch Road on Saturday afternoon, the burglar fled.

The woman said she ran after him, trying to keep him in view while desperately trying to get through to a 911 operator on her cellphone.

The incident that left Kathleen Burke physically bruised and psychologically frustrated came during one of three burglaries Saturday in two upper Northwest neighborhoods generally regarded as quiet and safe.

At least one link existed among the three, according to D.C. police. All “involved UNLOCKED doors,” a police lieutenant wrote on a community Web list.

The upper Northwest Washington area west of Rock Creek Park is generally regarded as being mostly free of violent crime. Of the offenses that do occur, including thefts from autos and burglaries, police say that many involve unlocked doors.

Mary Boesman, a neighborhood watch captain, said “it’s amazing how many times” she hears of incidents in which burglars have entered “through an unlocked window [or] an unlocked door.”

To some degree, the practice of leaving doors open may suggest that a strong sense of security exists among residents. Nevertheless, Boesman said police are tireless in warning against it.

“I can’t imagine why” people don’t lock their doors, she said.

The two other unlocked-door burglaries reported Saturday occurred in the 4400 block of Warren Street NW, west of Tenley Circle. According to a police report, one occurred between midnight and 8 a.m. and the other between 3 and 4 a.m.

Details of those incidents were not available immediately.

Burke, the Broad Branch Road resident, acknowledged that her door was open.

She was at home, she said, and “in the middle of Saturday afternoon, going back and forth doing yard work and stuff, you usually don’t lock your door.”

The first indication of the burglary came when her doorbell rang twice, Burke said. In retrospect, she said, it was apparently the burglar trying to see whether the house was occupied.

Then, after hearing the door slam and going to check, she said, she found a man in her house, “rifling through a desk drawer.”

“What are you doing?” she screamed. “Get out of my house! Get out of my house!”

The man brushed past her, heading for the door. Then, just as he was about to leave, she said, he wheeled around, grabbed her and tried to fling her to the floor.

She resisted, and “I’m probably lucky he didn’t break my wrist,” she said. As it turned out, it was merely bruised.

As the two scuffled, she said, “with all my force,” she threw a sharp elbow to his ribs.

Then he was out the door. But now, Burke said, her “adrenaline had kicked in,” and the chase began down Broad Branch and onto Morrison Street. Pulling her phone from her pocket, she said, she kept after him, all the while trying to reach a 911 operator.

Nobody picked up, she said. “I am stunned.”

She said she could not say how many times she heard a recorded message. But, she said, “it was multiple times.”

After she finally got through, she said, the D.C. police arrived swiftly, but the burglar apparently managed to get away.

It was not clear, she said, whether anything was taken from her house.