Karim, a 23-year-old student and one of my closest friends, has been arrested. On 4 August he was one of almost 30 people who decided to wear white and walk in one of the main streets of Damascus. It wasn't a demonstration as such – there were no placards or slogans, just white clothes and a silent walk. White was a colour with no political connotations, and walking in the same clothes helped them express their shared sadness at the turn of events in Syria. Despite that, Karim and couple of other friends disappeared.

I was at home when John, a mutual friend, called to inform me of Karim's arrest. "You shouldn't try calling him," he told me whisperingly on the phone, as if lowering his voice would hide it from the tapping devices rumoured to be placed on all mobile phones in Syria. "Let's try to see if we can get him out tonight."

My father, eavesdropping on the conversation, asked me what was wrong. When I told him what had happened he announced in his matter-of-fact tone that my friend "deserves it" for joining the criminal forces attacking "peaceful and beautiful Syria". He continued that my friend should have been concentrating on his studies or his work rather than bothering his brain with politics.

My father is a fan of the national Syrian TV channels and their reports about "criminal gangs" disturbing the cities of Syria. He sees nothing wrong with the army taking over the cities; his logic is that the army would never attack the honest people of Syria but is simply bringing peace to cities disturbed by the conspiracies surrounding our country.

Our group of friends, regardless of their political affiliations, went into crisis mode after Karim's arrest; contacts were called and people started working to get him out. But with the first Friday of Ramadan just a few hours away, all the people in power were busy preparing for the awaited day and no one was interested in working to get our friend out.

Many of our contacts thought it was some kind of sick joke. "He was arrested for what exactly?" a well-connected relative of mine asked. There was a moment of silence when I told him it was for wearing white and walking the streets, before he pulled himself together and continued the conversation.

On Friday evening I meet Karim's mother for the first time. She is seated behind her laptop wearing her reading glasses and her phone doesn't stop ringing. She keeps a brave face for a while, welcoming us to her house and presenting us with sweets while calling her son a batal (hero).

She jokes with us about extra sweets when her son gets out, but suddenly, her voice breaks and her eyes filled with tears.

Saturday morning comes and still Karim is missing. John is tired after a sleepless night getting phone calls from the mother of Mohamed, another friend who got arrested for the same reason in the same street. Mohamed's mother knows nobody and has no contacts; she cries every time she hears John's voice. John can find no words to make her feel better; he listens to her, telling her that there is no news, she cries, he listens, she hangs up then calls again 15 minutes later.

Karim's mother is roaming her house silently, tired from hearing one lie after the other. Everyone is spreading rumours. Some say our arrested friends are being treated well, others speak of blindfolded eyes and violence.

"He is not getting out today," John tells me and I agree. We have a quiet hope that maybe Karim will be out by Sunday – but Sunday comes and goes and our friend is not out.

Karim's mother tells me she might be able to send clothes and food to her son through a contact. We wait for the contact to call and the hours linger.

The phone rings but it's only a relative. As Karim's mother speaks, I see the tears slowly sliding down her face and I think of my own mother: how would react she if she was in the same position, who would she call?

I excuse myself and lock myself in the shower, crying for her and for my friend that I miss so much, for my city that is turning grey and for my feeling that I can't do a thing to help him.

Locked inside my own thoughts, I find myself overwhelmed and I excuse myself. I leave the house and walk out into the streets of Damascus, empty like a ghost city, put a song on my iPod and sing along to it.

I did not notice how high my voice was getting singing a silly sad song until some security informant stopped me and asked me, in his deep voice, while putting a heavy hand on my shoulder, what I'm singing about. I explain that I lost the love of my life and I'm singing my sorrows. Thinking that I'm hopelessly romantic, the security guy makes fun of me then lets me go.

On Monday, Karim's mother is roaming her house screaming and chanting slogans asking for the regime to fall; she wants her son back and she wants her revenge.

We wait for a phone call telling us that Karim is soon to be released, but all of our phones are silent and all our hopes are crashing. As I leave her house after hours waiting for news, I pass a clothes shop and stare at a white T-shirt for a while. Then I go inside and buy it.

Update, 26 September 2012: This article appeared under a pseudonym because of concerns for the writer's safety at the time. He has now left Syria and his real name is Ahmed Danny Ramadan.