Guatemala's chief of national police and the country's top anti-drugs official have been arrested over alleged links to drug trafficking.
Attorney General Amilcar Velasquez said police chief Baltazar Gomez and Nelly Bonilla were being held in connection with a cocaine theft in March 2009.
Mr Velasquez said five police agents were killed as a result of the theft.
Mexican drug gangs have been moving operations into Guatemala as they come under pressure in their own country.
The two most senior officials in Guatemala's fight against drug trafficking were arrested on charges of conspiracy to commit a crime, illegal possession of weapons and obstruction of justice.
"The captures were the result of tracking the investigation into the drug robbery that took place in Amatitlan, which those detained today are believed to have participated in," Mr Velasquez said.
The arrests come two days after President Alvaro Colom removed Interior Minister Raul Velasquez from office over alleged corruption.
With the US secretary of state about to visit Guatemala, the state department has published a report expressing serious concerns about corruption and inadequate law enforcement in Guatemala.
With Mexico making strong efforts against drug traffickers, Washington fears the cartels are moving south to take advantage of lax policing and limited surveillance in Guatemala, says the BBC's Julian Miglierini in Mexico City.