Jodi Arias carefully planned killing, Arizona prosecutors say By Tim Gaynor PHOENIX (Reuters) - Prosecutors seeking to convict Jodi Arias of murder for killing her ex-boyfriend told an Arizona jury in closing arguments of an often lurid trial on Thursday that she meticulously planned the slaying and then lied to cover her tracks. The 32-year-old California woman could face the death penalty if convicted of murdering Travis Alexander, whose body was found in the shower at his Phoenix valley home in June 2008. He was shot in the face, stabbed 27 times and had his throat slit. Arias has admitted killing Alexander, whom she dated for several months and with whom she continued having intimate relations even after their break-up. She said she killed him in self-defense after he attacked her in a rage because she dropped his camera. Prosecutor Juan Martinez, in summing up at the close of the high-profile trial, said Arias started planning the killing in late May 2008, at the same time a .25 caliber handgun - the same caliber weapon used in the slaying - was stolen along with other items in a robbery at her grandparents' California home. Arias said she shot and killed Alexander, 30, with his own pistol, and that she only became aware of the theft after it occurred. The weapon used in the killing has never been recovered. Martinez told the jury that Arias also rented a car in California and bought five-gallon containers and filled them with gasoline to fuel her journey to the Phoenix suburb where she killed Alexander. "The only reason to keep this whole thing a secret ... is because she is going to kill him, and she's making preparations, and she's very good at making these preparations," Martinez told the jury at the Maricopa County Superior Court. "It is like a field of lies has sprouted around her as she sat on that witness stand ... every time she spat something out, another lie, another weed would grow," he added. Earlier on Thursday, Judge Sherry Stephens told jurors they could consider the charges of first- and second-degree murder or the lesser charge of manslaughter. First-degree murder requires proof of pre-meditation. Since the trial began in January, Martinez has portrayed Arias as a jealous lover who set out to kill Alexander because she had been spurned. He told the jury that Alexander had sent an instant message weeks before his death saying he was "extremely afraid" of Arias because of her "stalking behavior." Martinez said Alexander also called Arias "the worst thing that ever happened" to him, and sent her a text message in which he called her a "sociopath." Do we need to look at the picture of his gashed throat ... do we need to look at his face where she put that bullet ... to know that what he says then is true, that you are the worst thing that could have happened to him? Martinez said in an address to Arias, who appeared close to tears. The closing statements are set to continue Thursday afternoon. Reporting by Tim Gaynor; Editing by Cynthia Johnston and Steve Orlofsky