Fourteen activists from Hong Kong were arrested Wednesday after seven of them landed on one of the disputed Senkaku Islands in the East China Sea, adding more fuel to the already heated territorial row.

The seven activists who landed on the islet of Uotsuri at 5:31 p.m. were met by about 30 Japan Coast Guardsmen, police and immigration authorities who had arrived beforehand. Two of the seven returned to their vessel while the other five were interrogated by immigration officers and arrested on suspicion of illegal entry, Okinawa police said, adding that nobody was injured on either side.

A few hours later, nine more activists aboard the vessel, including members of the Hong Kong media, were also arrested for the same offense, the coast guard said.