By Michael Bristow
BBC News, Beijing
Patients' dormitory rooms are as tidy as those at a military camp
For patients at Beijing's Youth Psychology Development Centre, the day begins with the loud blast of a whistle at about 0600.
They roll out of bed and quickly change into military fatigues before lining up in the corridor, ready to start the day's activities.
The mostly male youngsters at this centre all have the same problem - they are addicted to the internet.
And through a tough programme of physical exercise, medication and counselling, this is where they hope to be cured.
There has been a lot of interest in these boot camps over recent weeks after two teenagers were beaten up at two separate camps in China. One died, the other was seriously injured.
Tao Ran, the director of the Beijing centre, denies that camp workers use violence against his patients.
He said: "We use love and science to look after and cure our patients, to allow them to go to school and use the internet in a healthy way."
But the centre he runs is certainly no holiday camp.
It is run by a hospital attached to the Chinese military, the People's Liberation Army, and is on a military base.
As the young people go through their daily activities, real soldiers clean their rifles outside a dormitory next-door.
Locked rooms prevent the youngsters from leaving the boot camp
The patients - all teenagers or in their 20s - are sent to the centre because their parents believe they spend too much time on the internet.
Mr Tao defines an internet addict as anyone who is on the internet for at least six hours a day and has little interest in school.
Slogans posted on the walls of the centre make it clear that spending too much time on the internet is not healthy.
"Those who are masters of the internet are heroes," reads one, before adding, "Those who are controlled by the internet are slaves."
Youngsters come to the centre from across China and many of them have to endure its tough regime for three months.
'Father cheated me'
That regime starts with early morning exercises on the base's parade ground.
After that the addicts are brought back to their quarters - which they are locked into - where they have to tidy up.
Four people share each of the rooms, which - when put in order - look just like soldiers' dormitories.
Duvets are folded neatly on beds, flannels are hung over washbowls and four toothbrushes stand in cups, all pointing in the same direction.
According to the parents, few youngsters want to come to the centre to be cured - and it is not hard to see why they object.
Patients have to follow orders; one centre worker physically turned a youngster around when he was not paying attention at a roll call.
"My father cheated me to get me here. He said we were going out to have fun, but then he brought me here," said one teenager.
"At first I felt very unhappy, but later on I understood why my parents wanted me here. They want me to get rid of my internet addiction."
But at the centre it is not just the youngsters who have to reform.
Part of director Tao's approach is to change the way the whole family behaves; he believes it is not just the internet user who has a problem.
Many parents accompany their children to the Beijing boot camp in an attempt to learn how to better bring up their offspring.
And some of them admit that they do have something to learn.
"When we arrived and started listening to Dr Tao, we realised there were problems with our parenting, particularly with me," said one father, Chen Lin.
"We treated our child like an underling. We believed our child should do whatever we told him to do."
Mr Chen said he used to beat, abuse and make fun of his son to encourage him to work harder - now he says that was wrong.
"We hurt his feelings and he became less confident," admitted Mr Chen.
China's government has become increasingly concerned about how these boot camps are run - and their lack of oversight.
At the moment there is no national register of camps, and none of them have been approved and inspected by government officials.
The ministry of health issued a notice in July banning the use of "electro-stimulation" that was being used to "cure" internet addicts.
But worried parents across China continue to send their children to the camps.
As one father at the Beijing centre put it: "There's no other choice - this is our last hope."