(CNN) -- Some headlines are hailing her as the bravest woman in Mexico. Marisol Valles Garcia, all of 20 years old, says she's just tired of everyone being afraid.

Valles Garcia, a criminology student, became the police chief this week of Praxedis G. Guerrero, one of the most violent municipalities in the border state of Chihuahua. She was the only person who accepted the top job in a police force whose officers have been abducted and even killed.

"Yes, there is fear," Valles Garcia said Wednesday in an interview with CNN en Español. "It's like all human beings. There will always be fear, but what we want to achieve in our municipality is tranquility and security."

There's good reason for the fear. Just this past weekend, a 59-year-old local mayor, Rito Grado Serrano, and his 37-year-old son, Rogoberto Grado Villa, were killed in a house in which they they were hiding in nearby Ciudad Juarez. Another area mayor was killed in June.

Juarez is the bloodiest city in Mexico, with a reported 2,500 people killed in drug violence this year. Praxedis G. Guerrero is located about 35 miles southeast of Ciudad Juarez. Both are in the state of Chihuahua, which borders Texas.

Nationwide, the federal government says, more than 28,000 people have lost their lives since Mexican President Felipe Calderon declared war on the drug cartels after taking office in December 2006.

Valles Garcia sees a non-violent role for her 13-member force, which will be mostly female and unarmed.

"The weapons we have are principles and values, which are the best weapons for prevention," she told CNN en Español. "Our work will be pure prevention. We are not going to be doing anything else other than prevention."

Valles Garcia said she aims to establish programs in neighborhoods and schools, to win back security in public spaces and to foster greater cooperation among neighbors so they can form watch committees.

She has recruited three other women to join the force in the small municipality of 8,500 people, the government-run Notimex news agency said this week.

Valles Garcia said Wednesday she gladly accepted when Mayor Jose Luis Guerrero offered her the job. The first couple of days have gone smoothly, she said.

"Truthfully, we have been very tranquil," she said. "The people have received us very well. They have even supported us. They say it's a great project and they will be with us 100 percent."

Still, the notion of a largely female police force being helmed by a woman -- and a young one at that -- does not seem to sit well with some people in a country that still retains vestiges of machismo.

"Are there no men in Chihuahua?" read a headline on a blog on the Periodista Digital website.

But Valles Garcia believes what the job may need is a woman's touch.

"We are simply going to talk with them, with the people, with the families, giving them confidence so they will quit being afraid, so they can leave their houses," she told CNN en Español.

"We have hope that we are going to exchange fear for tranquility and security."