A U.S. conservative think tank says North Korea has exported more than one-thousand Scud missiles to Middle Eastern countries.

The Claremont Institute made the claim in a report titled, “Missile Defense, the Space Relationship and the 21st Century.”

The institute quoted the Nuclear Threat Initiative as saying that North Korea exported more than one-thousand Scud missiles, along with missile-related parts, to the Middle East.

The institute said missile exports, which net North Korea around one-and-a-half billion U.S. dollars a year, constitute one of its largest sources of revenue.

The report also said the North is suspected of providing Iran and Syria with key technology for the production of ballistic missiles.