Facundo Cabral of Argentina was on his way to Guatemala's airport when gunmen attacked his vehicle. The 74-year-old singer and novelist was shot at least eight times. His concert promoter was also wounded.
Some evidence suggested that the killing was not a simple robbery. Cabral was riding in a truck that tried to flee the attackers by driving into a fire station. He was accompanied by a second vehicle carrying bodyguards, according to a Guatemalan television station.
Police said agents apparently found one of the vehicles used in the attack abandoned along the highway to El Salvador. It said it was pocked with bullet holes and spent cartridges were found inside.
Cabral rose to fame in the early 1970s, mixing political protest with literary lyrics. He created deep bonds with an audience struggling through an era of revolution and repression across Latin America.
Cabral gave his last concert Thursday in the city of Quetzaltenango, west of Guatemala City.
The motive for the shooting is still unclear.
The Associated Press contributed to this story