SEOUL, South Korea (AP) — South Korean police said Saturday they beefed up security at the U.S. ambassador's residence in Seoul after a group of anti-American students used ladders to break into the compound.

They were protesting demands by the Trump administration that South Korea pay more to help cover the costs of keeping U.S. troops in the country.

Officials from three Seoul police stations didn't immediately say whether they will seek to formally arrest any of the 19 university students who were detained Friday afternoon at the residence of Ambassador Harry Harris.

The Seoul Metropolitan...