When Mr Mohamed Tahri returned to his office yesterday afternoon, the two plain-clothes policemen from the central commissariat were waiting in the stairwell. Tall, wiry young men with hard faces, they hovered by the door as we talked inside. The baby-faced 46-year-old human rights lawyer seemed no match for them. With his fur-edged black lawyer's gown hanging on a hook behind him, Mr Tahri whispered.
As police broke up a demonstration by the families of `disappeared' people earlier this week, he recounted softly, they tried to corral him into a side street.
"I looked down that street and I saw there was no one in it - only policemen. I was afraid I would be kidnapped, that I myself would become a `disappeared one'.
"So I started shouting, `I'm a lawyer. I defend human rights. You have no right to hinder my movements.' I took out my professional ID card and repeated, `I'm a lawyer.'
"There was a high-ranking police officer in a suit and tie. He pushed me back so I couldn't leave. Policemen surrounded me.
"The police officer said: `You are not a lawyer. You are a traitor because you have contact with foreigners and so-called human rights organisations.' When he saw I refused to go the way he was trying to make me go, he said, `Take him in.'
"They took me to an office in Cavignac commissariat. I know people who have died under torture at Cavignac.
"From there I was taken to the central commissariat in Boulevard Colonel Amirouche, where they held me six hours. They kept saying to me: `You have contacts with journalists. You have contacts with Amnesty International.'
"They said to me at Cavignac, `You are the one who gave information to Amnesty International and other organisations. You are the one who causes trouble in this country'."
Mr Tahri's international reputation, and immediate appeals by Human Rights Watch and Amnesty International, probably saved him - this time. Had the police threatened him before releasing him on Monday night? I asked.
"The threat is permanent."
Yesterday a woman from the Anasser district of Algiers came to tell Mr Tahri that three of her neighbours had been picked up by police on their way to the demonstration. Forty-eight hours later, their families could obtain no news of them.
The woman was reporting the disappearances from Mr Tahri's office to the International Federation of Human Rights in Paris when the telephone went dead.
Nearly 200 foreign journalists who have come to Algiers to cover today's nationwide local elections are also coping with phone tappers and inquisitive policemen.
When I left my files and newspapers in disarray in my hotel room, I came back to find them neatly stacked. But in the wrong order.
"You are completely free to talk to anyone you want to," an official told me. "Anyone?" I asked incredulously. "Well, anyone in the legal parties," he answered.
"And the illegal parties?" I continued, now stepping into dangerous waters. "You can't talk to them," he scowled. "They don't exist."