(CNN) -- A Florida man accused of killing a teenager in 2012 following a dispute over loud music testified during his trial Tuesday that he fired his pistol only after a passenger in an SUV repeatedly threatened him and that the passenger had what appeared to be a 12- or 20-gauge shotgun.
"I thought I was going to be killed," Michael Dunn testified.
Dunn, 47, is charged with first-degree murder in the fatal November 2012 shooting of 17-year-old Jordan Davis in a gas station parking lot in Jacksonville, Florida. The teen and his friends were sitting in an SUV next to Dunn when an argument quickly led to Dunn pulling his gun and shooting nine times into the vehicle, killing Davis.
Police say no weapons were recovered from the teenagers' vehicle. Dunn acknowledges killing Davis, but told police he acted in self-defense after seeing what he believed to be the barrel of a shotgun or a stick in the teens' red Dodge Durango.
Dunn testified that, after parking in the lot so his fiancee could buy wine and chips at a convenience store, he asked the passengers in a nearby SUV to turn down what called "ridiculously loud music" with a thumping bass.
The music stopped at first, and Dunn thanked them, he testified. But the music resumed, and an SUV passenger said, "I should kill that motherf*****," and then, louder, "I should f****** kill that motherf******," Dunn testified.
Dunn, sitting in his vehicle, lowered his window again and asked the passenger whether he was talking about him, the defendant testified.
The passenger reached down and picked something up and "slammed it against the door ... and said, 'Yeah, I'm going to f****** kill you,' " Dunn testified, adding he could see about 4 inches of what looked like a shotgun barrel above the SUV windowsill.
The passenger then cracked open the SUV door and said, "You're dead, bitch," and, when the passenger's head cleared the window frame, added, "This s*** is going down now," Dunn testified.
Dunn said he feared for his life and started getting his pistol out of his glove box. He testified that as he did so, he said, "You're not going to kill me, you son of a bitch."
Dunn's testimony came after the prosecution rested its case Monday following four days of testimony.
Dunn also faces three counts of attempted first-degree murder related to three other teens -- Leland Brunson, Tommie Stornes and Tevin Thompson -- who were in the vehicle with Davis but survived the shooting.
Dunn has pleaded not guilty to all the charges.
Assistant State Attorney John Guy, speaking for the prosecution, told jurors in opening statements last week that Dunn asked the teens to turn down their music, and Jordan disrespected him, saying, "F*** that n****r" -- nothing more -- and for that, Dunn opened fire, hitting Jordan three times.
HLNtv.com's Amanda Sloane and CNN's Eliott C. McLaughlin contributed to this report.
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