Estate Place in Loudoun County is a gently curving cu-de-sac street of large and well-spaced single-family houses. But unnerving events may occasionally happen, as indicated by a report from the county sheriff’s office.

It was 10 minutes after midnight Tuesday morning in the 21400 block of Estate Place, in the Ashburn area of the county, according to the report, when a door opened in one of the houses there.

An intruder, a resident told the sheriff’s office, looked inside.The intruder was male. The resident did not know him, the sheriff’s office was told. And, according to the resident’s account, the stranger who opened the door wore a ski mask.

But, when the intruder saw the resident, the intrusion ended, according to the sheriff’s office. The intruder fled, the sheriff’s report said. No injury was reported, and nothing was reported taken.

The matter is being investigated as an unlawful entry, the sheriff’s office said.

Estate Place intersects Farmwell Road (Route 640) just west of the Ashburn Ice House, a skating rink.