The structure appeared in the Banda Lingua commune, prompting some to take selfies with it, though others had a more negative reaction, according to residents.

Cisco, Kimba, Angola Hey said police have been posted to protect the monolith from youths who wanted to remove or destroy it.

It's late last year monolith was discovered in the United States, generating much excitement among science fiction fans who likened it to Stanley Kubrick's 1968 film 2000 and one A Space Odyssey.

Since then, others have emerged one of the World Heritage site in Turkey earlier this month, for example, another in a mountainous area of Romania last December.