North Korean coal exports hit their highest level in five years in April, before which no data is available, according to Chinese customs figures.

In recent years coal has been the DPRK’s most valuable export, though falling prices in 2015 could have hurt the DPRK’s trade revenues.

In April however, North Korean exports to China jumped by more than 20 percent, to nearly 2 million tonnes. According to the data, the extra shipments garnered North Korea nearly $120 million, up from $80 million in the previous month.

“(The) North might have tried to sell more coal