Reuters: International inspectors have found traces of sarin and VX nerve agent at a military research site in Syria that had not been declared to the global chemical weapons watchdog, diplomatic sources said on Friday.

Samples taken by experts from the Organisation for the Prohibition and Chemical Weapons (OPCW) in December and January tested positive for chemical precursors needed to make the toxic agents, the sources told Reuters on the condition of anonymity because the information is confidential.

“This is a pretty strong indication they have been lying about what they did with sarin,” one diplomatic source said. “They have so far been unable to give a satisfactory explanation about this finding.”