article_snippet.sent: A drone carrying small traces of a radioactive material landed on the roof of Japanese Prime Minister's office in protest against the government's nuclear energy plans.
article_snippet.sent: The drone was equipped with a small camera and a plastic bottle containing small traces of a radioactive material, according to Japanese media.
article_snippet.sent: The drone, which landed on the roof of the Japanese Prime Minister's official residence, was found to contain traces of a radioactive substance .
article_snippet.sent: The radioactive material is likely caesium, a soft metal and harmless to the human body, Tokyo Metropolitan Police said.
article_snippet.sent: The radioactive material is not known who flew The drone onto the building but The radioactive material is widely suspected The radioactive material was someone protesting against Japan's nuclear policy.
highlights_snippet.sent: Remote control device had miniscule levels of radioactive substance .
  