CHARLESTOWN, Ind. — What is left of Pleasant Ridge, a neighborhood of prefabricated World War II-era homes, sometimes belies its mellifluous name. Some of these tiny duplexes are battered by wear, holes in their sides. Dogs growl in cluttered yards. On a recent early afternoon, a woman stumbled down a street here muttering curses, as the words “Call your officer now!” emanated loudly, again and again, apparently from her ankle monitor.

Leaders of Charlestown, a city of 8,000 in southern Indiana across the Ohio River from Kentucky, say it is time to remake the Pleasant Ridge section of town. These homes, built for workers at a local Army ammunition plant, were never meant to be permanent, they say, and are simply unsafe after more than 70 years.

Beyond structural problems, city officials say the neighborhood draws a disproportionate share of the city’s crimes, drug problems and animal control issues, including a fair number of raccoons that like to hide in the hollowed-out nooks and crannies of the aging structures.

But signs have been popping up on homes here, among the crush of American flags, porch chairs, old bikes and wind chimes: “Not for Sale,” “Hands Off My Home,” “Save Pleasant Ridge.” Residents say the city is suddenly targeting their neighborhood with skyrocketing code violation fees that swiftly run into thousands of dollars, as an end-run to close the whole place down, wipe it away and build something fancy.

Residents of the neighborhood, who say it is one of the few places in Charlestown with rentals available for $400 or $500 a month, say the code violation crackdown is meant to drive out people who do not make much. With the opening of a new bridge between Louisville, Ky., and this part of Indiana, these residents say, Charlestown leaders are dreaming of transforming their city into a high-end bedroom community for that far larger city.

“They don’t want you if they think you’re poor,” said Ellen Keith, as she cut a client’s hair at Hair & Such Beauty Salon.

“Before all this, I thought we were all equal. I thought I lived in a mansion,” said Ms. Keith, who has lived for four decades in a pristine, painstakingly decorated Pleasant Ridge home with her husband, Dave. “But this is all about who is rich and who is poor, and now people around here look at us differently based on our address. It breaks our hearts what’s happened.”

On Friday, residents who hope to save Pleasant Ridge filed a request for a preliminary injunction in state court, aided by the Institute for Justice, a libertarian public interest law firm that sees what is happening here as a troubling new way for a city, in essence, to clear land.

“What’s very unusual about this is using code enforcement to circumvent eminent domain law,” said Jeff Rowes, a lawyer in the case, which asks a judge to stop the city. “And we’re worried about this becoming a model — the model for how to replace housing for people of modest means in states everywhere that have passed limits on the powers of eminent domain.”

The city of Charlestown, where the crest outside City Hall’s storefront office reads “Generations of Pride,” vehemently rejects such suggestions. Michael Gillenwater, the city attorney, says what is happening in Pleasant Ridge, where a private developer has begun accumulating lots, is all about safety, not wealth.

Many residents actually want to move somewhere else, he said, and Charlestown, where the median household income is about $43,600 a year, is working out alternatives to assist them. Claims about the city’s motives have been rife, he said, with false accusations, innuendo, supposition.

“We’re not going to ever make a dime on this,” Mr. Gillenwater said. “It’s a matter of helping out the city and the people in the long run. All we’re doing is trying to have safe housing.”

Mr. Gillenwater said that many of Pleasant Ridge’s 350 homes, without slab foundations, have deteriorated to a point that is untenable, and that they were never meant to last this long in the first place.

“Look, the mayor grew up in a trailer — he didn’t grow up as a wealthy person,” Mr. Gillenwater said of Bob Hall, the mayor, who has been seen as the driving force behind change at Pleasant Ridge. Mr. Hall did not respond to requests for an interview.

“This is not about rich and poor,” Mr. Gillenwater continued. “When you’ve got the crime, the drugs, animals running about, this is about life and death.”

A walk through Pleasant Ridge, where the curving, narrow streets have no sidewalks, reveals a study in contrasts. Along some blocks, children ride bicycles beside elaborately adorned porches and well-tended homes, and neighbors stop to talk. But nearby, one duplex has holes in its windows, and another is smashed and boarded up, damaged by a car that careened into it not long ago.

There is a reason different parts of Pleasant Ridge feel so different. For some families, generations have grown up here and residents know all their neighbors; a few even speak of relatives who once worked at the ammunition plant. But in the decades after the ammunition plant closed, the makeup of this place changed. Many homeowners sold to landlords, and some rentals went untended.

“There’s no question that there are problems,” said Josh Craven, who lives here and is president of a homeowners association that has grown out of this fight. “But the city let this happen over all these years. They allowed the slumlords to come in, to not live up to the property maintenance code. They’ve let this go on so long that you can’t come in now and say, ‘Oh, you have to repair everything now or we’re going to fine you thousands of dollars every day so that you just have to sell to get out from under the debt.’”

The neighborhood is starting to empty. Some landlords with multiple property maintenance violations have sold their land rather than try to pay mounting fines for demands that they repaint, replace electrical outlets, improve the structure’s anchoring to the ground, or fix cracked windows and broken screens.

In a successful campaign for a City Council seat, Tina Barnes, one resident, spoke out against forcing Pleasant Ridge homeowners to move. She said she now found herself a lone voice on the council to save the place.

Ms. Barnes grew up here, and moved back to Pleasant Ridge a few years ago when she paid a cousin $9,500 for a duplex where her grown daughter, who is disabled, and two grandchildren also live.

“It was like coming home for me,” she said. “I never thought anyone looked down at us. Honestly, until all this came out, making it all sound so bad, I never thought of us as different.”