News reports said investigators believed the suspects planned to contaminate water supplies in the capital, including the commercial area around Via Veneto where the U.S. Embassy is.
One of the four Moroccans arrested Tuesday is believed to be linked to a suspected Milan-based terrorist cell that was dismantled last year with the arrest of seven Tunisians, news reports said. The Tunisians, now on trial in Milan, are suspected of having ties to Osama bin Laden's al-Qaeda network.
In phone conversations wiretapped before their arrests, the suspects talked of a drug, referring to it as "tomato cans"–believed to be a well-used code name for cyanide, according to Italian authorities.
But Chief Prosecutor Salvatore Vecchione said police identified the compound as potassium ferrocyanide, which contains small quantities of cyanide. The compound was being analyzed, he said.
Ferrocyanide, harmless compared to cyanide, is used in the production of wine and ink dye, among other uses, said Luciano Caprino, a pharmacology professor at Rome's La Sapienza University.
He said small amounts of cyanide can be extracted from ferrocyanide but that it is an extremely difficult procedure.
Tuesday's raid was described as the biggest probe so far into suspected Islamic terrorist activity in the city. In January 2001, the embassy was closed to the public for three days because of a terrorist threat, its first closure in about a decade. Three other Moroccans were arrested in the capital last week as part of the same investigation, reports said.
Embassy officials declined to make a statement regarding the ongoing investigation.
Source: USA Today