TRUCKEE, Calif.  When Mimi Ash arrived at her mountain chalet here for a weekend ski trip, she discovered that someone had broken into the home and changed the locks.

When she finally got into the house, it was empty. All of her possessions were gone: furniture, her son’s ski medals, winter clothes and family photos. Also missing was a wooden box, its top inscribed with the words “Together Forever,” that contained the ashes of her late husband, Robert.

The culprit, Ms. Ash soon learned, was not a burglar but her bank. According to a federal lawsuit filed in October by Ms. Ash, Bank of America had wrongfully foreclosed on her house and thrown out her belongings, without alerting Ms. Ash beforehand.

In an era when millions of homes have received foreclosure notices nationwide, lawsuits detailing bank break-ins like the one at Ms. Ash’s house keep surfacing. And in the wake of the scandal involving shoddy, sometimes illegal paperwork that has buffeted the nation’s biggest banks in recent months, critics say these situations reinforce their claims that the foreclosure process is fundamentally flawed.