Italian police have arrested 28 Pakistani men suspected of links to Al Qaeda in one of the biggest anti-terrorism operations in the country, even as the Pakistan embassy described the arrests as part of a campaign ‘‘targeting innocent Pakistanis living in Italy’’.Military police burst into an apartment in central Naples on Wednesday night as part of a routine sweep against illegal immigration and ended up discovering enough explosives to blow up a three-storey building, officials said today.They arrested all 28 men staying in the apartment after finding 800 grams of explosives, 70 metres of fuse and various electronic detonators crammed behind a false wall.Islamic religious texts, photos of ‘‘jihad martyrs’’, piles of false documents, maps of the Naples area, addresses of contacts around the world and more than 100 mobile telephones were also found in the run-down lodgings, police said.A judicial source said the maps had various targets marked out on them, including the headquarters of NATO command, the US Consulate in Naples and a US Naval base at Capodichino, just outside the Port city. Lieutenant Colonel Pat Barnes, a spokesman for US European Command in Stuttgart, Germany, said protection levels at all US naval facilities in Italy were raised one notch on Thursday night as a result of the arrests. In a statement, the police said they believed the men, aged 20 to 48, were members of Al Qaeda network.‘‘The men have been arrested and charged with association with international terrorism, illegal possession of explosive material, falsification of documents and receiving stolen goods,’’ the statement from Naples police headquarters said.Police said the explosive material was sufficient to make a bomb capable of blowing up a three-storey building and that some of the fuse was laced with highly flammable nitroglycerine.As well as the religious texts written in Urdu, cuttings of Pakistani newspapers and manuscripts repeating the phrase ‘‘God is great’’ were found.Pakistan’s ambassador to Italy, Zafar Hilali, denied the men were terrorists and said the arrests appeared to form part of a campaign of targeting innocent Pakistanis living in Italy. ‘‘According to my information none of (these men) had anything whatsoever to do with terrorism, none of them had anything like explosives,’’ he told Pakistan TV.‘‘The embassy immediately applied for access to our citizens and I myself asked to see the minister of the interior because this is not the first time such allegations have been made. There are reasons these kinds of charges are levelled against our people and you can best judge what they are.’’He said 24 of the 28 men had applied for permits to work in Italy and were legal, adding that they were unfortunate only because they were living in a house owned by the Mafia.In nearly 18 months since the September 11 attacks, more than 100 people have been arrested in Italy on suspicion of links to terror organisations. Seventeen have been convicted, but most have been released for lack of evidence.Police have grown wary of touting what appear breakthroughsin the fight against terrorism, and sources said magistrates were irritated that news of the latest arrests had leaked.At the same time, the evidence police say they have collected seems much greater than in previous operations of the kind. (Reuters)