Most of the tapes date from the Shia Muslim insurgency that erupted after the first President George Bush urged Iraqis to overthrow the former Iraqi leader in the wake of the 1991 Gulf War.

Many of the executions took place in Najaf and Karbala.

Some of the tapes show a man who appears to be Lieutenant General Ali Hassan al-Majid, a cousin of Saddam Hussein, better known as "Chemical Ali", killing people.

A BBC correspondent who has seen some of the recordings says they are evidence of the atrocities of the former regime.

On Monday, a mass funeral took place in Iraq for unidentified victims of the 1991 Shia uprising.

A communal grave containing the remains of hundreds of people was discovered three weeks ago in Makhazan, near Najaf, which is the Shia branch of Islam's holiest city.

After a funeral procession through the city, the remains were reburied near the grave of the Shia Imam, Mohammad Baqer al-Sadr, known as the White Lion, who was executed in 1980.

Suffering under Saddam

One vendor said Iraqis buying the tapes of executions wanted to see for themselves what happened during Saddam Hussein's regime. This is normal. People have suffered a lot of tragedies from Saddam Hussein. I don't know whether people believe these things or not. I don't know," the vendor told the BBC Arabic service.

Psychologist Abd al-Muhsin al-Khayat said people might also want to buy the tapes out of morbid curiosity.

"There are many possible explanations," he said. "They might have a missing or a person who was executed, so they try to identify him through the tapes.

"The other explanation is that some young people like sensational things, whether they are positive or negative."

Last month, human rights workers in Iraq said they had found a number of mass graves containing the bodies of up to 100 civilians killed during the 1991 uprising.