LARNACA, Cyprus (Reuters) - Cypriot authorities detained a Lebanese national on Thursday after finding in his possession a large quantity of ammonium nitrate fertilizer which, police said could case widespread damage if used in an explosive mixture.
A public prosecutor, asking for court proceedings to be held in camera, said the case raised questions of state security.
Police said they had discovered two tonnes of ammonium nitrate at premises used by the 26-year-old in the coastal town of Larnaca on Wednesday night.
Ammonium nitrate is a fertilizer but in large quantities can be mixed with other substances to make a powerful explosive.
The find is unusual in Cyprus, which despite proximity to the Middle East has not seen a major militant incident since 1988 when a car packed with explosives blew up on a Nicosia bridge, killing 3. The car was meant to target the Israeli embassy.
Police declined to speculate on possible motives for hoarding the substance, found in more than 400 boxes in the basement of a home in a residential neighborhood of Larnaca. It was still being searched on Thursday.
The suspect, who a police source said also holds a Canadian passport, arrived on the Mediterranean island about a week ago.
"This is a very serious case," a police spokesman said.
Judicial authorities accepted a police request that proceedings be held behind closed doors.
"This is a case which pertains to the security of the state and public disclosure could possibly adversely affect those interests," a public prosecutor told the judge.
The suspect, a young man of medium build with short cropped hair, was led handcuffed by police into a courtroom. He sat emotionless in a grey t-shirt and jeans.
Cypriot media carried unsourced reports that the individual maintained to police the ammonium nitrate was not his.
(Reporting By Michele Kambas; editing by Ralph Boulton)