It is said in Malabo that the screams coming from inside the city's police headquarters are sometimes so loud that they wake nearby residents in the middle of the night.

"More often than not they are of women being raped and beaten," one Western official in Equatorial Guinea told The Times during a rare visit to the country four years ago.

For a few hours in September 2004, I had the dubious pleasure of getting to know this building from the inside after being arrested during a trip out of the capital into the lush interior of the tiny nation.

While The Times's photographer and myself were kept in a side room by ourselves, our translator was thrown in a cell so overcrowded that everybody was forced to stand. Rats scurried about and a solitary bucket overflowed with excrement.

It was only after the intervention of the British consul that our seven hours in police custody were brought to an end, but the justice minister - who arrived at the scene to make sure we were freed - took great delight in telling us how "lucky" we were.

The head of the secret police, who accompanied him, put on an exhibition as we walked away, leaving the door wide open as he repeatedly whipped a drunk prison guard.

It was the end of a week in which I had been stopped by police on several occasions, one of whom openly threatened me as he gesticulated wildly with a flask of whisky in one hand.

At a time of nationwide paranoia following the coup attempt earlier that year, President Teodoro Obiang Nguema, a man said to eat his enemies' testicles and known by his subjects as "the Father behind the Gates", had ordered his security forces to be on high alert.

One soldier pulled me out of a taxi and ordered me to tear up my notebook. On our trip out of Malabo, our car was waved over as we left a provincial town and we were ordered inside a police station.

We were told that we had the "wrong" travel permit to go outside of Malabo. Our translator was taken to a separate room and accused of "conspiring" with foreigners. After several hours we were escorted back to the capital and to the police headquarters.

However bad the conditions at Malabo police headquarters - where desperate faces poke through the cell bars as you leave - they are as nothing compared to the city's notorious Black Beach jail, where prisoners are left to what Amnesty International calls "a slow, lingering death sentence".

Torture - including burning and beating the soles of the feet - is said to be routine. If Simon Mann is taken to Black Beach, he will join the handful of plotters, mostly South Africans, who are serving up to 34 years in connection with the 2004 alleged coup attempt.

Standing in a vast auditorium doubling as a courtroom, these men looked emaciated and exhausted as they shuffled in and out - their hands and ankles in shackles - during their trial in 2004.

They have since complained of poor food, lack of medical help and beatings. One of their number died a few days after being taken to Black Beach. The official explanation for his death was that he had contracted cerebral malaria; however, other prisoners said that he had been tortured.

Times Recommends

• Over the Wall
• Why Africa welcomes the ‘new colonialism’
• Which will come out on top: paper or gold?