North and South Korean troops exchanged fire along their tense border on Sunday, the South's military said, blaming North Korean soldiers for targeting a guard post. Violent confrontations have occasionally occurred along the border, the world's most heavily fortified. While Sunday's incident is a reminder of persistent tensions, it didn't cause any known casualties on either side and is unlikely to escalate, observers say. The Joint Chiefs of Staff in Seoul said in a statement that North Korean troops fired several bullets at a South Korean guard post inside the heavily fortified border. South Korea fired two rounds in response after issuing a warning broadcast, it said. South Korea suffered no casualties, the military said. It's unknown whether North Korea had any casualties. The North's official Korean Central News Agency hasn't reported about the incident. South Korea said it was trying to contact North Korea via a military hotline to avoid an escalation. It comes a day after North Korea broadcast images of leader Kim Jong-un reappearing in public after a 20-day absence amid intense speculation about his health. KCNA said Kim attended Friday's ceremony marking the completion of a fertilizer factory near Pyongyang along with senior officials. State TV showed Kim smiling and walking around factory facilities.

The Anchorage airport, Alaska's largest, temporarily shut on Saturday to inbound traffic because of a bomb threat against a China Airlines cargo flight bound for Asia. The cargo plane diverted to Ted Stevens Anchorage International Airport early in the morning after leaving Seattle, airport officials said. No bomb was found and the airport was reopened shortly before noon, officials said. The plane was searched in a secure, remote section of the airport, the airport said in a statement, with the Federal Bureau of Investigations and Anchorage Police Department. "After extensive investigation, no explosive device was located," the airport’s police and fire department said in a statement. "Investigation at the airport has been completed, however, the investigation into the source of the threat continues. The FBI does not believe there is any continuing threat to our community as a result of this incident.” The Anchorage Daily News said the plane was headed to Taipei, Taiwan and the threat had been called into the Port of Seattle, quoting an FBI spokesman who said investigators were still trying to determine the source of the threat. China Airlines, Taiwan's largest carrier, said in a statement the flight had already taken off for Taipei when it was informed of the threat by Seattle airport. The plane was then diverted to Anchorage. The crew were taken to a hotel to rest while police searched the aircraft and determined nothing unusual, it added. The aircraft is expected to land in Taipei late Sunday evening, China Airlines said. Anchorage Airport is one of the world’s top five air-cargo hubs. It ranks second in the nation for weight of landed cargo. It ranks 58th in passenger travel among US airports. While passenger flights have been sharply curtailed during the coronavirus pandemic, air cargo operations are considered by the state to be essential and have continued. Flights that could not land in Anchorage on Saturday morning were advised to consider diverting to the airport in Fairbanks, another cargo hub.

The reported appearance came after weeks of speculation over the North Korean leader's health.