An Army officer said he thought the rapid rate of gunfire meant there was more than one shooter in last November's Fort Hood massacre.

But when the shooting ceased after police brought down Nidal Hasan, it became clear he had acted alone, Major Stephen Richter said.

Richter of the Army Medical Corps recounted in chilling detail how he could feel the shooter stalking him as he saw the red laser from Nidal Hasan's gun sight flickering in his eyes.

Testifying via video link from South Korea, Richter said Hasan was distracted by gunfire from the civilian police and turned away from him.

He said he called out when he saw Hasan's uniform and identification badge.

"I remember saying to the police officer – 'he is one of us,'" Richter said.

Still convinced there were other shooters after Hasan was down, Richter said he grabbed Hasan's handgun off the ground and prepared to fire it. But the gun was jammed, and as he tried to clear the it, he burned his fingers on the barrel, which was still hot after hundreds of rounds had been fired.

The prosecution plans to complete presenting its case Thursday in the Article 32 hearing to determine if Hasan should proceed to court-martial. The defense has been told it can start its case November 8.

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