According to Ecuadorian Col. Luis A. Rodríguez, commander of the Ecuadorian forces defending the province of El Oro during the war, the incidents of 5 July started when an Ecuadorian border patrol found some Peruvian civilians, protected by policemen, clearing a patch of land on the Ecuadorian side of the river. Upon seeing the patrol, the Peruvian policemen opened fire, killing one soldier. This was followed by the widespread exchange of fire between troops on the opposing banks of the Zarumilla, while two Ecuadorian officers sent to Aguas Verdes to speak with the Peruvian local commanding officer were told by Peruvian authorities to go back to their lines.