Six Americans were detained on Friday in South Korea for trying to send 1,600 plastic bottles filled with rice, US dollars bills and Bibles toward North Korea by sea, police said.
The Americans tried to throw the bottles into the sea from frontline Gwanghwa Island so they could float toward North Korean shores by the tides, said a police officer who spoke on condition of anonymity because he was not authorised to speak to the media on the issue.
He said they were being investigated on allegations that they violated the law on the management of safety and disasters.
A second South Korean police officer confirmed the detentions of the Americans.
The police officers gave no further details, including whether any of the six had made previous attempts to send bottles towards North Korea.
Activists floating plastic bottles or flying balloons carrying anti-North Korea propaganda leaflets across the border has long caused tensions on the Korean peninsula.
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South Korea suspends propaganda loudspeaker broadcasts along border to North Korea
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