(CNN) -- Ecuador is calling for British authorities to help investigate after officials found a secret recording device planted inside the South American country's embassy in London. A "spy microphone" was found inside the Ecuadorian ambassador's office on June 14, Ecuadorian Foreign Minister Ricardo Patino told reporters Wednesday. It was hidden inside a small white box inside an electrical outlet, partially covered by a bookshelf, he said. The discovery, Patino said, "very seriously concerns us." "We are requesting backing from the British government to continue with the investigation of the device found," he said. The device, he said, contained a SIM card and was designed to transmit private conversations occurring inside the embassy. Ecuadorian authorities believe it had been in place for weeks.
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Ecuador says a hidden recording device was found inside its London embassy
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The "spy microphone" was placed in an electrical outlet, the foreign minister says
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He calls for British authorities to assist in Ecuador's investigation
It was found two days before @placeholder was scheduled to arrive at the embassy, he said.