A Tucson man told jurors he was "scared out of his mind" when he shot and killed a stranger in a road-rage incident.

Benny Alvarez Casarez, 50, was within an arm's length of Andres Buelna's truck when the 25-year-old closed his eyes and fired his .40-caliber handgun, Buelna testified Wednesday.

"He could've grabbed my firearm. He could have opened my door and pulled me out, and who knows what would've happened after that?" a tearful Buelna said.

After firing the gun, Buelna said, he opened his eyes, didn't see the man and left.

"I was terrified," Buelna said. "I was scared out of my mind, and I wanted to get away from the whole situation."

Buelna is on trial in Pima County Superior Court on a second-degree-murder charge.

His attorneys, Michael Piccarreta and Louis Fidel, hope to persuade jurors that Buelna acted in self-defense. Prosecutors Victoria Otto and Danielle Constant contend Buelna intentionally killed Casarez despite having many opportunities to avoid the situation.

Buelna told jurors he was on his way to his girlfriend's house on Aug. 1, 2011, when he decided to stop at the Albertsons on North Campbell Avenue near East Glenn Street. He went to change lanes but was forced to swerve back when he realized a Ford Mustang was there.

"The next thing I noticed, the Mustang came up really fast behind me and was right up on my behind," Buelna said. "I tapped my brakes so he would give me some space."

Almost immediately, Casarez pulled into the center turn lane to pass him, Buelna said. The man made an obscene gesture and mouthed something at him before swerving in front of him, forcing him to make an evasive maneuver.

As the two vehicles got closer to East Fort Lowell Road, Buelna decided he was going to turn into the Jack-in-the-Box to get away from the situation. However, as soon as he turned on his blinker and got into the turn lane, Casarez, who was still in front of him, did the same.

Buelna told jurors he decided that if Casarez turned into Jack-in-the-Box, he would continue on and turn west onto Fort Lowell.

Believing the Mustang to be nearly past the entrance to the restaurant, Buelna said, he began to turn into the parking lot. At that point, he heard the Mustang's tires screech and saw Casarez make a sharp turn into the parking lot.

Since he was already in traffic, Buelna said, he couldn't back up, and there were cars traveling southbound so he had no choice but to finish making his turn.

He couldn't drive past the Mustang because Casarez was already out of the car and in his path, Buelna said.

"He jumped out of his car, threw his hands in the air and he said he was going to "(expletive) me up," Buelna said.

Buelna testified he displayed his gun and fired a warning shot several feet over the man's head, but he continued to advance.

It was at that point, Buelna said, he closed his eyes and fired the gun.

Buelna was arrested at a local hotel the next night.

During cross-examination, Buelna acknowledged that he shot an unarmed man and that the incident started when he almost hit Casarez. He also acknowledged Casarez wasn't the only one yelling and giving obscene gestures.

"You gave as good as you got, didn't you?" Otto asked Buelna. "Yes, ma'am," Buelna responded.

Jurors are expected to hear closing arguments this morning.

Judge Scott Rash is presiding over the trial.

If convicted, Buelna faces between 10 and 22 years in prison.

Contact reporter Kim Smith at 573-4241 or kimsmith@azstarnet.com On StarNet: Follow the news and events at Pima County's courthouses in Kim Smith's blog, At the Courthouse, at azstarnet.com/courthouse