North Kosovo is a part of Kosovo largely inhabited by ethnic Serbs who generally consider themselves to be part of Serbia, not Kosovo.
EULEX is a European Union agency intended to assist Kosovo with its police, judiciary, and customs.
EULEX established these two North Kosovo border crossings last December. This February these drew protests from local ethnic Serbs, who viewed them as a threat to their connection with Serbia, not Kosovo.
In its latest action EULEX announced, as of May 20,
EULEX Customs will start copying the IDs of drivers of incoming commercial vehicles only, and will take copies of any commercial documents accompanying the loads. In addition, to reduce the amount of fraud and smuggling at the Gates, EULEX Customs Component will also stamp a copy of the commercial document. Copies of all data and documents taken by EULEX will be shared with its counterparts in Kosovo and Serbian Customs.
In response, President of the Serb National Council of Northern Kosmet Milan Ivanovic stated that he expected Belgrade to respond to EULEX's copying and that there would be a "sharp reaction."
We should note that Kosovo generally is a region notorious for organized crime and smuggling; so there probably is fraud and smuggling at these two gates. On the other hand, when the local population is actively hostile to efforts to control customs, these efforts probably won't work very well.