Michael Dunn, the man charged with fatally shooting 17-year-old Jordan Davis at a gas station in Jacksonville said he only fired his weapon because he feared for his life, the Associated Press reported.

After the defense rested its case during Tuesday's hearings, prosecutors brought Rhona Rouer, Dunn's fiancee, back to the witness stand, according to the AP.

While on stand, Rouer contradicted Dunn's statement about telling her he saw a barrel of a gun in the back window of the SUV, the AP reported.

During his testimony, Dunn said he shot Davis after seeing a barrel of a gun while they argued over the loud music being played from the SUV, the AP reported. No signs of a weapon was found in the SUV.

"I couldn't believe what I was seeing and hearing," Dunn said, adding that he attempted to calm the situation with the three teens in the SUV, who, according to Dunn bore "menacing expressions," the AP reported. The incident occurred in November 2012.

After the shooting, Dunn drove back to the hotel where he and his fiancee were going to stay and did not call the police, the AP reported. According to Dunn, he was more worried about tending to Rouer.

Rouer convinced Dunn to drive back to their home in Brevard County, about 175 miles away the next morning, which is when Dunn spoke to a neighbor in law enforcement, according to the AP.

Dunn has pleaded not guilty to charges of first degree murder, and cited self-defense when shooting the 17-year-old from Georgia, the AP reported. Closing arguments were expected Wednesday.