Two North Korean Soldiers Cross the MDL

Could this have been a deliberate provocation, a defection attempt, or neither?

Two North Korean soldiers crossed a stream some 20-30 m into the South in
Hwacheon, Gangwon Province at around 12:47 p.m. on Friday but returned to the
North when South Korean troops fired warning shots. This is the first time in
five years the South Korean military has had to fire over the heads of North
Korean soldiers crossing the Military Demarcation Line (MDL). The last time was
in September 2001.

Yes, North Korean soldiers posted to the DMZ do defect. I actually met one of them recently.