Ecuador has arrested six Colombian nationals in connection with the assassination Wednesday of Ecuadorian presidential candidate Fernando Villavicencio.
Another suspect, also Colombian, died from wounds sustained in a shootout with police.
Villavicencio, known for speaking out against drug cartels, had reported that he had received death threats.
"The national police now have the first arrests of the alleged material authors of this abominable event and will employ all of their operative and investigative capacity to discover the motive of this crime and its intellectual authors," Interior Minister Juan Zapata said.
Ecuadorian President Guillermo Lasso said the killing would not stop Ecuador from holding the presidential vote Aug. 20.
Lasso has asked for FBI help in the investigation of the shooting of Villavicencio. An FBI delegation is expected to arrive in the country soon.
Some information for this report came from Reuters and The Associated Press.