The North Korean flag flies above the country's embassy in Beijing last month. China is the North's most important trading partner and ally, but lately Beijing has been placing pressure on Pyongyang over the North's nuclear and missile programs.
North Korean leader Kim Jong Un attends the combined fire demonstration of the services of the Korean People's Army in celebration of its 85th founding anniversary in a photo released on April 26.
KCNA via KNS /AFP/Getty Images
An official photograph dated April 15 and posted by the Navy shows the aircraft carrier USS Carl Vinson in an Indonesian strait thousands of miles south of North Korea.
MC2 Sean M. Castellano/U.S. Navy
Royal Malaysian Police Chief Khalid Abu Bakar addresses journalists in front of a screen displaying the details of North Korean Embassy staffer Hyon Kwong Song, who has been identified for questioning, during a press conference at the Bukit Aman police headquarters in Kuala Lumpur.
Manan Vatsyayana/AFP/Getty Images
Kim Jong Nam, the estranged half-brother of North Korean leader Kim Jong Un seen here in a May 2001 file photo, was alleged assassinated at the Kuala Lumpur airport last week.
Noor Rashid Ibrahim (left) of the Royal Malaysian Police speaks about one of the North Korean suspects, with Selangor state police chief Abdul Samah Mat looking on, in Kuala Lumpur on Sunday.
Mohd Rasfan/AFP/Getty Images
TV screens in Seoul, South Korea, show images Wednesday of Kim Jong Nam, the half-brother of North Korean leader Kim Jong Un. On Monday, Kim Jong Nam was killed in Kuala Lumpur, Malaysia.
Kim Jong Nam, the half-brother of North Korean leader Kim Jong Un and the eldest son of former leader Kim Jong Il, waves to reporters on the Chinese island of Macau in 2010.