Leaders from more than 50 countries and international organizations are attending the Nuclear Security Summit in The Hague from March 24 to 25, with the focus on nuclear security and the prevention of nuclear terrorism.

Just ahead of the summit, the Democratic People's Republic of Korea (DPRK) fired 30 short-range rockets into the sea off the east of the Korean Peninsula early on Saturday. The rockets, which are believed to be old Soviet-developed FROG rockets that the DPRK has had since the 1960s, flew for 60 km before crashing into the sea, Yonhap said. One week ago, the DPRK had fired 25 short-range rockets into the sea off its east coast. It's widely believed the short-range-rocket launches by the DPRK this month are an "armed protest" against the ongoing annual ROK-US military drills.

The DPRK's launching rockets in protest against ROK-US military drills in fact is nothing new, which has highlighted the difficulty in resolving the DPRK nuclear issue.