11 men were shot dead in Cape Verde on Tuesday, including eight soldiers, a local civilian and two Spanish citizens, the minister of Internal Administration for the archipelago off the African coast said in a statement.
The men were killed at a telecommunications site at Monte Tchota, a forested area on Santiago island about 27 km (17 miles) north of the capital, Praia, Minister Paulo Rocha said.
Rocha said it was assumed personal motivations were behind the killings, ruling out an attack against the government, and called for calm.
The Spaniards were telecommunications technicians working at the site and the local civilian was a co-worker, the minister said.
The minister said there were no indications of links to drug trafficking.
Cape Verde's battle against gangs smuggling Latin American cocaine to Europe has led to a series of reprisal shootings. The former Portuguese colony is an Atlantic Ocean archipelago of 500,000 people off the northwestern coast of Africa
Nine rifles were taken but were later recovered in a vehicle in Praia's Cittadella neighborhood, Rocha said.