This appears to be the same bomb as this one dropped by the Myanmar airforce against the rebels in the province of Karenni.

This has been identified as a 250kg FAB bomb of Serbian origin sold by through the Sloboda company to the Myanmar new governement.
Myanmar Air Force also bought 20 Soko G-4 Super Galeb armed jet trainers from Yugoslavia in 1991 .
This same bomb seems to be seen on the ground in this display of the armament on the G-4 , rear rank, inner position (click to enlarge)
and a better view of the bomb of the first post from its original report (click to enlarge for High resolution):
Title "
Karenni Army officers are seen with the bomb in question after digging it out of the earth in Sawng Dula village, Demoso Township, Karenni state (KNDF)"

"....further examination of the unexploded bomb in Karenni State could confirm its country of origin [Serbia], noting that the major components differentiating bombs’ manufacturers were apparent in the design of the tails, as well as possibly in lettering on the device. ... the two red bands marked on the device suggest that the bomb could be a type of incendiary weapon, but was not able to identify the bomb accurately with the photos and data currently available...