Syria's government says people who fled rebel zones that have since been retaken by the military are now welcome to return. But that's not how it worked out for one refugee family that came to check out the state of their home: They found another family had moved in.

That's just one of many hurdles keeping away those displaced in Syria's war.

Many who fled say they fear arrest if they return to homes now under government control or that their sons will be conscripted into the same military that once bombarded their towns. In other former opposition strongholds, the state is carrying out redevelopment projects that have razed thousands of homes.

The opposition accuses the government of President Bashar Assad of using under-the-radar methods to discourage populations it sees as disloyal from returning, changing the demographics to help consolidate control over a corridor running from Damascus to the Mediterranean coast.

The government says it is doing all it can to bring people back.

"The main goal of the Syrian government is to return all displaced Syrians to their homes," National Reconciliation Minister Ali Haidar told The Associated Press last month.

More than 11 million people, nearly half Syria's population, have been driven from their homes by the war since 2011, including 5 million who fled abroad as refugees.

The war still rages in many parts of the country, and there is heavy destruction. In those conditions, a mass return is unlikely. So it is difficult to measure how much government measures are keeping opposition-minded Syrians from returning.

But the fall of a number of opposition strongholds in recent months has brought to immediate relevance the issue of who can come back.

For example, a string of rebel, mainly Sunni Muslim suburbs around Damascus have come under military control. They were drained of much of their population as hundreds of thousands fled siege and bombardment in recent years. Now thousands more are leaving because of government control. It is an open question whether they will ever return.

In Aleppo, Syria's largest city, government forces are besieging the rebel eastern districts, and the estimated 275,000 residents have refused calls to evacuate, in part because many are convinced they'll never be allowed back.

The fact that most of the people from rebel areas are Sunni Muslims adds a toxic sectarian aspect to the charges of demographic manipulation. Sunni Muslims are the majority in Syria and make up the backbone of the rebellion, while minorities have largely supported Assad, particularly members of his own Alawite community, an offshoot of Shiite Islam.

Homs, Syria's third largest city, offers an indication of the hurdles for would-be returnees.

In 2014, Homs' last major rebel neighborhoods, centered in its Old City, surrendered. That came after a long brutal siege that drove an estimated 300,000 from the city.

Two years later, the government says the Old City is open for residents, but even official statistics say only 40 percent have returned. That figure is impossible to independently confirm, and the opposition believes it is inflated.

On a visit to the Old City of Homs earlier this year, an AP team found a ghost town.

More recently, AP interviewed six families expelled from Homs' old quarters, and only one could point to a relative, among hundreds, who has returned. All those interviewed spoke on condition they only be identified by their first names for fear of reprisals by the government.

"The families of the old city are still in exile. Today, you'll find them all over the world, except in their neighborhoods," said Abou Zeid, from the George Chiyah neighborhood.

Hoda, now living in the Lebanese city of Tripoli, said she was told she had to pay overdue bills before she could see her Homs home. But she, like others, is deeply hesitant to approach state institutions to do so or validate her property records because it means crossing through multiple checkpoints run by the feared security services.

The displaced fear security forces will detain their husbands and sons for trumped-up crimes or conscript them into Assad's military.

"We are not able to go back," said Rabaa, who fled to Lebanon with her family in 2012.

She has a 20-year-old son. "The first thing they'll do is take him to the military," she said. "Go see our home? No way."

Families have also found others living in their homes. The extent of such incidents is murky. The displaced say the expropriation is widespread, but their reports cannot be independently confirmed.

A pair of sisters, Maha and Um Alaa, described to the AP how they tried to check on Um Alaa's apartment in the town of Tel Khalakh, a former opposition stronghold 25 miles (40 kilometers) east of Homs. The sisters, now in Tripoli, spoke on condition they not be fully identified.

Maha visited and found another family living there, she said. A loud argument ensued, and Maha backed off, fearing that the government would side with the squatter family.

Um Alaa said her neighbors told her the family was from the nearby town of Hosn. Neighbors also said other displaced people had asked authorities in Tel Kalakh for places to live and were directed to houses of those who had fled, Um Alaa said.

The family in the home could not be reached because the landline has been switched off.

Also, Um Alaa fears she and her husband won't be able to reclaim their home because they didn't bring their property deed when they fled in 2014. "We thought we would only be gone a month," she said. "We have nothing to prove it is ours."

Conscription fears are also driving residents out of former opposition strongholds.

The government denies that conscription is a tactic to push dissidents out, saying it a national duty.

"It's a law that dates back to the establishment of the Syrian state," said Haidar, the national reconciliation minister.

He said the military is exploring ways around the predicament. For example, in some recaptured areas, the government has offered to postpone conscripts' deployments for six months to a year.

But many deserters and draft-dodgers view this as simply a government tactic to give them a deadline to leave.

"The implication is that ... in these six months you get everything in order and flee, (and the military) will look the other way," said Dani Qappani, an opposition activist.

In the Damascus suburb of Moadamiyeh, for example, a third of the population of 50,000 fled during the government siege. After the suburb surrendered in September, some 10,000 more are likely to leave over the coming months for fear of conscription, said Bassma Kodmani, an opposition official.

Similarly, some 13,000 will probably leave the Damascus suburb of Qudsaya along with their families to avoid conscription, said a former fighter in Qudsaya.

The fighter, who is wanted for military service, said he approached authorities for the 6-month grace period and received it. He said that gives him time to sell his home and belongings before moving with his wife and two children to the northwest province of Idlib, the main rebel-held territory. He spoke on condition of anonymity because he has not yet left the government-held area.

When the suburb of Daraya fell in August, all its last remaining residents — around 2,700 from an original 250,00 — were removed and put in camps, raising an outcry from U.N. officials over the possibility of a forced displacement. The government says they will eventually be allowed back.

But Daraya could see the sort of urban renewal projects that observers say are also a tool for demographic engineering.

A 2014 report by Human Rights Watch identified seven opposition neighborhoods around the country razed by government authorities for "redevelopment." It accused authorities of carrying out collective punishment.

Presidential Decree 66, issued in 2012, lists a number of areas, mostly opposition, for urban renewal projects involving demolishing shantytowns.

"It serves another purpose: to punish the unruly areas, so you pacify them, and you change the demographic," said Rashad al-Kattan, a political analyst affiliated with the Center for Syrian Studies at the University of St. Andrews, in Scotland.

In March, Assad lay the cornerstone for one such renovation project, in Damascus' working-class Kafr Sousa and Basateen al-Razeh neighborhoods. The project is to build orderly new residential towers. But opposition outlets say residents are being pushed out. The Human Rights Watch report said up to 3,000 residential buildings had been demolished.

Decree 66 also authorizes similar projects for Daraya, according to the pro-government business journal Iqtisad.

Daraya and the other Sunni suburbs are highly strategic, said Kodmani, with the opposition's High Negotiations Committee.

"If Damascus is to be really safe over the longer term, any pockets around Damascus need to be made loyal."