In some cases, people have been woken by officials knocking on the door in the night and given just hours to pack their belongings and leave.
Others have had their water and electricity cut off, at a time when temperatures regularly drop below zero, and been told their apartment blocks and businesses would be demolished days later.
Technically, this is part of a city-wide safety campaign, after a fire killed 19 people - including eight children - last month.
But critics accuse the authorities of using the fire as an excuse to drive out the migrant workers who come to the capital from other parts of the country, as part of a long-term plan to cap the city's population.
The scale of the evictions and demolitions is staggering.
In Xinjian village, on the southern outskirts of Beijing, we found a wasteland of sheer destruction.
Large swathes of what was a busy neighbourhood have been demolished, heavy machinery working slowly through the rubble, grinding down the remains of countless abandoned homes.
We met a family wheeling their suitcases down a deserted street, the rest of their accumulated possessions in plastic bags.
They said they had nowhere else to go but back to their home village in central China. They didn't know what they would do for there for work.
Another group stood in the cold with their luggage by the side of the road, hoods drawn tightly against the bitter wind. The garment factory where they worked is being demolished.
"We have no [dignity]," Lu Huayun told us. "That phrase about the China dream is not true for us. That excludes us. It's not fair for us."
Another man said it had happened so quickly he had been forced to sleep in a car overnight.
"Some people had too many things to carry, factories sold their machines, they couldn't take all their things away in time," he said.
"Local residents were packing up and moving while the demolition was happening at the same time," he said.
He was too frightened to give his name, adding: "There are a lot of policemen in the village. They will take you away if they catch you speaking to media."
It didn't take long for us to find the police patrols, or rather for them to find us.
As our cameraman filmed, two officers in stab vests and helmets, followed a few steps behind him. It wasn't exactly subtle.
But then it started to more sinister.
As the Sky News team tried to leave, a number of policemen, accompanied by men in plain clothes, blocked the road in front of the car.
Our driver tried to reverse, but they were behind the vehicle too, preventing it from moving.
After a brief stand-off, they relented, but clearly this is not a story the authorities want told.
News of the evictions is being censored in China, as is the term "low end population" which officials now deny ever using, despite references in documents posted online earlier this year, apparently since deleted.
But the migrant workers' plight is resonating across different levels of society here.
Author Lijia Zhang told us she is outraged by the way they are being treated, many of whom have made substantial personal sacrifices to do low paid jobs in the city in the hope of building a better future for their children.
"In my view, they are the unsung heroes of China's economic miracle," she explained.
"They staffed production lines, they constructed the buildings, they paved the highways, collected the rubbish, and looked after our children, we cannot survive without them.
"As a human being I just feel horrified that they have been treated like this."
More than 100 intellectuals signed a public petition, calling for the evictions to stop, and an end to the "discrimination and humiliation".
But the petition has since been removed.
Beijing municipal authorities insist they are not targeting migrant workers, merely unsafe, illegal structures.