A court heard dramatic and emotional testimony on the first day of the “American Sniper” trial.

Chris Kyle’s widow Taya took the stand, where she tearfully testified about the day she learned that her husband had been killed. She told the court that she called Kyle while he was driving up to the shooting range and could tell something was up because he was quiet, as if he couldn’t talk because others were around. Later, she said she texted him, but got no response.

The defense attorney for alleged killer Eddie Ray Routh revealed that Kyle drove to the range, and his friend, Chad Littlefield, sat in the passenger seat. Routh was seated in the backseat.

The attorney also discussed a text message from Kyle to Littlefield, which said, “This dude is straight up nuts.” Littlefield texted back, “He’s right behind me, watch my six,” which means “cover my back.”

The defense is trying to prove that Routh was legally insane when he killed Kyle and Littlefield at the shooting range. But the prosecutor told the jury that Routh admitted that he used drugs, drank whiskey and knew what he was doing was wrong.

Graphic photos of the victims’ bodies were also shown in court.

The murder trial is expected to last a few weeks.