MADRID, Spain (CNN) -- Suspected Islamic extremists arrested last week in Barcelona were planning al Qaeda-style attacks in Spain, Germany, France, Britain and Portugal, according to an informant who "infiltrated" the group, Spain's El Pais newspaper reports. "If we attack the metro [subway system in Barcelona], the emergency services can't get there," one of the suspected suicide bombers told the informant, El Pais reported on Saturday. "Our preference is public transport, especially the metro." El Pais reported that it had access to the informant's testimony to Spanish officials. CNN has confirmed that authorities have given high importance to an informant's testimony.
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Informant: Terrorists planned to attack public transport systems in Europe
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El Pais said it had access to informant's testimony to Spanish officials
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10 suspects were arrested for allegedly plotting attacks
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Informant: Cell consisted of six suicide bombers
Two other pairs of suicide bombers were to strike elsewhere in Spain, while another suicide bomber was to attack in @placeholder, although the informant said he did not know where or when those attacks were to occur, El Pais reported.