(LONDON) -- Spanish police arrested three suspected al Qaeda operatives on Wednesday out of fear they were planning an airborne attack in Europe, Spain's interior minister, Jorge Fernandez Diaz, said Thursday.
Spanish police have arrested dozens of alleged militants since 2004, when a key Madrid train station was attacked, but Spanish media reported these were the first caught with explosives -- meaning they had become an operational cell.
The three suspects -- two from ex-Soviet republics and a Turk -- had timers and enough explosives to blow up a bus, Diaz told a press conference in Madrid.
At least two of those arrested had practiced flying light aircraft -- believed to be a motorized paraglider, according to Spanish newspaper El Pais. Diaz called one of those arrested a "very important member" of al Qaeda who is an expert in explosives and poison.
"It is one of the most important operations against al Qaeda to date to be carried out on an international level," Diaz said. "There are clear indications that the suspects arrested could have been planning an attack in Spain, and or, other European countries."
Diaz described the two suspects from ex-Soviet republics -- believed to be Chechnyan -- as al Qaeda members and said they were arrested as they traveled on a bus, possibly to cross into France.
"Police moved to arrest them when it became known that they planned to leave Spain," he said.
Diaz said the Turk, who he described as a facilitator, was arrested in a house in the southern town of La Linea, where the explosives were found.
Diaz said non-Spanish, international investigations aided in the operation.
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