小型无人机落日本首相官邸屋顶

Japanese authorities have launched an investigation after discovering a small drone on the roof of Prime Minister Shinzo Abe\'s office.

The four-propeller drone measured about 50 centimeters in diameter and was carrying a camera, a plastic bottle, and a flare-like device, according to national broadcaster NHK.

Several media outlets also reported the drone was decorated with a radioactive symbol, and the Kyodo news agency reported a small amount of radiation was measured on the craft.

Television footage showed dozens of police officers hovering around the drone, which was covered by a blue tarp.

It is not clear who sent the drone or what their motive may have been. There have been no reported injuries. Prime Minister Shinzo Abe was away from his office at the time, attending a conference in Indonesia.

日本NHK广播公司说，这架四旋翼无人机长约50厘米，装有一架照相机、一只塑料瓶以及一个类似照明灯的装置。

多家媒体还报道说无人机装饰放射性标志，而共同社报道飞行器上检测到微量辐射。

电视画面显示，数十名警察在盖着蓝色篷布覆的无人机周围徘徊。

目前还不清楚这架无人机的操纵者，也不清楚操纵者的动机。没有关于有人受伤的报道。安倍首相当时正在印尼出席一个会议，因此不在首相官邸。