A shipment containing a reported $2 million of cocaine was intercepted last week at the United Nations headquarters in New York, authorities revealed Thursday.

Around 35 pounds (16kg) of the drug was intercepted by security personnel at the building’s mail processing center, according to FOX News Channel.

The cocaine was reportedly stuffed inside a batch of hollowed out books and hidden inside two mailbags stamped with bogus UN logos.

With a probe underway, the world body insisted Thursday that none of its staff were implicated.

Police, meanwhile, were working on the theory the narcotics were probably dispatched to the UN by accident as part of a bungled drug smuggling exercise.

“The United Nations nor anyone located in the United Nations was the intended recipient of this delivery and the bags were not UN bags, diplomatic or other,” said a spokesman for Secretary-general Ban Ki-moon.

The bags were originally shipped from Mexico via a DHL center in Cincinnati, New York Police Department Deputy Commissioner Paul Browne told the AFP news agency.

“It is my understanding that because there was no addressee, the DHL just thought well that’s the UN symbol so we should ship it on to UN headquarters and let them figure out who it was supposed to go to,” Browne said.

“The working theory now is that possibly it was never meant to have left Mexico at all,” Browne said. The bags were “a bad fake.”

“Somebody in Mexico is probably in trouble now having let a significant amount of cocaine out of their possession,” the police chief added.

Earlier, a diplomatic source at the UN told FOX News the bags were delivered to the UN’s diplomatic pouch processing center with covers that mimicked those of official diplomatic pouches.

The same source said one working theory being considered by officials was that a worker at the processing center was the intended recipient.

The UN’s headquarters have been based in Manhattan, overlooking the East River, since 1952. Though it is in the US and subject to most local, state and federal laws, the land on which the complex sits is actually under the administration of the UN itself.