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SEOUL, Oct. 18 (Yonhap) -- The government requested Friday that law enforcement authorities beef up security around the U.S. Embassy and the residence of the top American diplomat in Seoul after nearly 20 university students trespassed in his residence.
Earlier in the day, 17 students and members of a progressive civic group broke into the residence of U.S. Ambassador Harry Harris in central Seoul by climbing over its wall using a ladder.
They staged a surprise protest criticizing Washington's demand for a hefty rise in Seoul's share of the cost for the upkeep of the 28,500-strong U.S. Forces Korea. Police took the 17 and two others attempting to join them into custody for investigation.
"Any harm to or attack on foreign diplomatic missions will not be justified under any circumstances," Seoul's foreign ministry said in a text message sent to reporters.
The ministry added that it would take "all appropriate measures" to protect areas surrounding foreign diplomatic missions and prevent any acts disturbing their well-being.
Police said they regard the break-in as a serious incident, saying that it will be sternly dealt with and that security around the residence will be intensified to prevent a recurrence.
The protest came as Seoul and Washington plan to hold another round of negotiations next week on how much South Korea will pay next year and beyond for the stationing of American troops on the peninsula.