The lives of an estimated half million people forcibly displaced in harsh security crackdowns across southeast Turkey have been devastated and left to uncertainty, Amnesty International said in a report on Tuesday, in what "may amount to collective punishment."

Turkish authorities imposed open-ended curfews in dozens of cities across the predominately Kurdish southeast in response to renewed fighting between the outlawed Kurdistan Workers' Party (PKK) and security forces following the breakdown of a ceasefire in July 2015.

For the first time in the nearly three-decade long conflict, armed PKK affiliated youth groups took the fight to urban areas, where they declared "self-governance," erected barricades and dug ditches. Turkish security forces responded with draconian force, destroying several towns and neighborhoods and imposing curfews. The government blames the PKK for the destruction.

One of the hardest hit areas was Diyarbakir's Sur district - a UNESCO world heritage site of tightly packed houses and ancient mosques and churches surrounded by the second largest city walls in the world.

The curfew in Sur began in December 2015 across several parts of the district, then expanded at its height in January to 15 neighborhoods. Six neighborhoods remain under curfew despite armed clashes in the area ending in March.

Nearly all of the 24,000 residents of the six neighborhoods under curfew have left, putting many in a precarious position of having lost their homes and jobs. Children's education has been disrupted, exacerbating already low education levels and ruining future prospects.

"A year after a round-the-clock curfew was imposed in Sur, thousands of people remain displaced from their homes, struggling to make ends meet and facing an uncertain future in an increasingly repressive atmosphere," said John Dalhuisen, Amnesty International's Europe Director. "Much of the population of this world heritage site have been forced to look on as their own heritage has been bulldozed."

Many of those displaced have nowhere to go after authorities expropriated most of the properties in Sur as part of planned "urban renewal projects." In some cases, the state has offered compensation, but Amnesty said it was inadequate. Those that return to their neighborhoods find their possessions destroyed.

A bulldozer clears housing and rubble in the Sur district of Diyarbakir.

"Displaced residents have been unable to find adequate alternative housing that is affordable and have struggled to access essential services," Amnesty said. "Grossly inadequate compensation and a failure by authorities to provide sufficient – or in some cases any – rent assistance has pushed already impoverished families into greater hardship."

The situation facing displaced residents in Sur is mirrored in dozens of other towns across southeast Turkey, Amnesty said.

For some families, it was the second time they were displaced. Several million Kurds from rural areas were driven into urban centers across Turkey during fighting between the PKK and security forces in the 1980s and 1990s. Diyarbakir's population alone doubled during this time.

Compounding civilians' plight is a broader crackdown on media, opposition and civil society in the wake of the July 15 failed coup attempt. President Recep Tayyip Erdogan has used emergency powers to crack down on Kurdish politicians, replacing dozens of elected mayors, including in Sur and Diyarbakir, with government appointments.

Turkish soldiers patrol next to historic Four Legged Minaret in the Sur District of Diyarbakir.

NGOs providing assistance to those displace have meanwhile been shut down on allegations of supporting "terrorism."

Fighting between the PKK and security forces in urban areas has largely stopped since the summer, but has continued in rural areas and the mountains. Amnesty called on the Turkish government to lift existing curfews, allow civilians to return to their neighborhoods and provide adequate compensation so that they can begin rebuilding their devastated lives.

During a visit to Diyarbakir in September, Prime Minister Binali Yildirim said the government would invest 577 million euros ($645 million) in Sur to turn its old buildings into modern habitable structures and attract tourists.

Many Kurds have long expressed the belief that the government's intent is not to provide security given that major fighting ended months ago. Rather, they worry the government plans to develop neighborhoods and resettle Kurds in other places.

A wide ranging 2012 urban renewal law developed in the wake of a devastating earthquake in the city of Van has been used for development projects in other parts of the country, particularly in low income areas with valuable real-estate, that have displaced residents. The projects are run by the state housing authority TOKI, which grants contracts to companies close to Erdogan and the ruling AK Party as part of a large patronage network.

"The current process across the region as a whole is suggestive of a premeditated plan to displace residents, destroy and rebuild the areas to ensure security through changes in infrastructure and transfers of population," Amnesty said in the report.