The website of local newspaper A Semana says two of the dead civilians are from Spain.
Security forces are on red alert at the international airport in Praia, the capital, and at the island’s ports after the apparent attack.
Government officials in the former Portuguese colony were reportedly planning a news conference later in the day after an emergency meeting of the Cabinet.
Besides domestic flights Cape Verde Airlines flies to several European cities in Portugal, France, The Netherlands, France and also the United States and Brazil. Thompson Airlines has flights from the U.K. to Cape Verde.
Cape Verde, or Cabo Verde, is an independent nation on a volcanic archipelago off the northwest coast of Africa. It’s known for its Creole Portuguese-African culture.
