This video comes from Yeomni Park.
Yeomni Park is a North Korean Defector and Advocate for freedom. She is now a US citizen and reports on news coming out of North Korea through a myriad of contacts.
She found this report released from the State propaganda news outlet, which is dated 2013.
So 300,000 + people go missing in a town - a bad smell is in the area - and 'UFO's' are seen.
Yes, there's an expert who can explain everything about the plague of Wonsan UFO's.
As one person in the comments made a guess - Nuclear reactor gone bad, chemical spill, town abandoned or people moved (or worse).
Let's blame it on UFO's and abductions.
YouTube: North Korea State Agency Confirms Shocking UFO Appearance in Wonsan City