ROME (AP) _ Security experts from the U.S. State Department will inspect a utility tunnel running alongside the U.S. Embassy here in connection with an Italian probe of a group of Moroccans suspected of planning a chemical attack, Embassy officials said Monday.
Italian authorities will join the U.S. experts Tuesday in the inspection of the tunnel where a hole was discovered last week, an embassy official said on condition of anonymity.
The tunnel, which runs under Via Boncompagni, a street flanking the Embassy compound, contains electricity and telephone lines, U.S. officials said. Italian news reports had said the tunnel also contains gas lines, but Embassy officials said that was incorrect.
Eight Moroccans were picked up in a police raid last week that also turned up nine pounds of a cyanide-based compound, firecrackers and maps of Rome highlighting the U.S. Embassy and the capital's water supply. A ninth turned himself in over the weekend in southern Reggio Calabria.
Italian news reports have said that investigators believe a chemical attack on the Embassy's water system was being plotted.
But the U.S. Embassy officials, who briefed reporters Monday, said there was ``no hard evidence'' of an attack being planned on the Embassy's water supply.
``There's a lot of circumstantial evidence,'' a U.S. official said. ``We don't know the aim'' of the Moroccans found with the chemical compound and the map.
Italian news reports said the hole was not in the tunnel in mid-January, the last time authorized work was carried out, but Embassy officials said it hadn't been ruled out that the hole might have been there earlier but was simply not noticed.
Police refused comment Monday.
In an initial appearance before a judge Sunday, the suspects denied being part of a terrorist group and said they didn't know how the chemical compound got into their apartment. The judge ordered that they continue to be held on charges of subversive association.
Defense attorney Domenico Martelli said Monday that he would appeal the judge's order. He also said the firecrackers were left over from a New Year's celebration.
Potassium ferrocyanide is a compound that includes small quantities of cyanide, a deadly poison. Officials are trying to determine whether it could have been used to make an explosive or dangerous gas.
Luciano Caprino, an expert in pharmacology at Rome's La Sapienza University, said potassium ferrocyanide itself is not toxic. But he said if the compound is heated to about 930 degrees it can emit highly toxic hydrocyanic acid.
``Depending on its density in a room, this gas could kill in a few minutes,'' he added.