Military officials accused of atrocities during Guatemala's civil war must be brought to justice to ensure that such crimes are not repeated, the country's attorney general said on Wednesday.

Retired army general Otto Perez, who swept to power in the November 6 presidential elections, will be the first military man to govern the Central American nation since decades of army-led dictatorships ended in 1986.

Perez, who commanded troops during the bloody 1960-1996 conflict, assumes power just as the attorney general's office is beginning to charge high ranking military officials for war crimes. He takes office in January.

We owe an enormous debt to all the victims of the war and if there is no justice, these crimes could be repeated, Attorney General Claudia Paz y Paz told Reuters on Wednesday.

Around 250,000 people, mostly ethnic Maya, were killed or disappeared during the conflict. A United Nations truth commission found that 93 percent of wartime human rights violations were committed by the armed forces.

Perez, a retired general, is under pressure to allow genocide cases against his former superiors to continue.

We want it to be clear that you can't use terror as a control mechanism, Paz y Paz said.

Perez was elected after pledging to root out gang violence and Mexican drug cartels that are ravaging Guatemala, which now has one of the highest homicide rates in the world.

In May, the powerful Zetas Mexican cartel beheaded 27 farm workers over a dispute with the farm's owner in one of the worst massacres since the end of the civil war.

Paz y Paz worried that budgetary constraints could interfere with Guatemala's efforts to uphold justice.

Guatemala has made important advances in the fight against organized crime ... but we are never completely prepared because we don't have sufficient resources, Paz y Paz said.

(Editing by Paul Simao)