Man on Fire

In 2003, burnt-out ex-CIA(SAD/SOG) Paramilitary operations officer and former U.S. Marine Corps Force Reconnaissance officer John Creasy (Denzel Washington) visits his old comrade Paul Rayburn (Christopher Walken), who runs a security firm in Mexico. Because of the extremely high rate of kidnappings in Mexico City for ransoms, wealthy businessman Samuel Ramos (Marc Anthony) hires Creasy through Rayburn to guard his nine-year-old daughter "Pita" (Dakota Fanning). Samuel however is having money problems, and intends to keep Creasy on only long enough to satisfy the requirements to renew his kidnap and ransom insurance on Pita. Creasy suffers from alcoholism, depression and severe guilt as a result of his former black ops work. Drinking heavily, Creasy attempts suicide with his pistol, but the bullet fails to fire when he pulls the trigger. He calls Rayburn, who says that "a bullet always tells the truth." At first Creasy distances himself from Pita, but soon he becomes a surrogate father to the girl, allowing him to stop drinking and find a purpose in his life.
While Creasy is escorting Pita to her piano lesson, a group of gunmen try to kidnap her. Creasy kills four of the kidnappers, including two corrupt policemen, in a shoot out, but he is shot multiple times and collapses from his wounds, and the abductors escape with Pita. Creasy is hospitalized but is moved to a veterinary hospital by Miguel Manzano (Giancarlo Giannini), an agent of the Agencia Federal de InvestigaciÃ³n (AFI), who suspects Creasy will be killed by rogue police. Meanwhile, the Ramoses agree to deliver a dead drop ransom of US$10 million per the instructions of "La Voz" ("The Voice") (Roberto Sosa), the mastermind behind the kidnapping ring. Samuel's attorney, Jordan Kalfus (Mickey Rourke), arranges for the ransom money to be collected from Samuel's kidnapping insurance policy, then delivered to the kidnappers. The drop, however, is ambushed by members of "La Hermandad", a powerful crime syndicate composed of corrupt police officers, who steal the money and kill The Voice's nephew in the process. The Voice notifies the Ramoses that Pita will be killed in retribution.
Creasy leaves the hospital before fully recovering, swearing to Pita's mother Lisa (Radha Mitchell) that he will kill everyone involved in her daughter's abduction. Rayburn helps Creasy purchase black market firearms, a rocket-propelled grenade and explosives. Mariana Guerrero (Rachel Ticotin), a journalist investigating kidnappings, and Manzano also offer their support. Creasy tracks down low-level operatives involved in various stages of the kidnapping, torturing each for information about other operatives, then killing them in brutal ways, eventually learning from the "president" of "La Hermandad" that the bags they stole at the ransom drop contained only $2.5 million of actual currency while the rest was blank paper.
Creasy finds Kalfus murdered and then finds evidence of his questionable financial dealings with Samuel. He confronts Samuel and Lisa for the truth behind the kidnapping. Samuel confesses to Creasy and Lisa that he agreed to Kalfus' plan to stage Pita's kidnapping, so he could pay off business debts by fraudulently collecting the insurance money. He planned to keep $5 million for himself and split the rest between Kalfus and the kidnappers. He was told that Pita would watch cartoons for a couple days and return after the ransom was paid. Samuel confesses to killing Kalfus, and Creasy leaves Samuel with a pistol and the misfired round, which works for Samuel when he commits suicide.
Using the information provided by Creasy, The Voice's identity is revealed by Manzano to be Daniel SÃ¡nchez, who Mariana exposes on the front page of her newspaper. Creasy sneaks into the home of SÃ¡nchez's ex-wife and children, and is shot by his brother Aurelio (Gero Camilo), whom Creasy then captures. Creasy calls Daniel SÃ¡nchez and threatens to kill all of his family unless he gives himself up, but SÃ¡nchez reveals that Pita is still alive, and offers her in exchange for Aurelio and Creasy. Creasy and Pita share a tearful goodbye before he surrenders himself to SÃ¡nchez' men, as Pita is released into her mother's arms. Creasy succumbs peacefully from his gunshot injuries. Daniel SÃ¡nchez is later killed by Manzano during an AFI arrest raid.

Question: What is the name of the journalist?
Answer: Mariana Guerrero