Months before his arrest in Russia, U.S. Army soldier Gordon Black made a surprise video call from his overseas tour in South Korea to his 6-year-old daughter in Texas.

Instead of a normal chat, however, his daughter and wife witnessed a fight break out between Black and his Russian girlfriend that became bloody, said his wife, Megan. Screaming turned to violence, with his girlfriend clawing at his face. Then she pulled a knife.

"She stabbed him," Megan Black told Reuters in an exclusive interview, saying Black "had blood on his face." Her daughter was distraught.

Black could not be reached for comment about the video call. 

The Army did not respond to a request for comment about his case. Reuters was unsuccessful reaching Black through the State Department.