Both girls claim they can see a spectre of a woman of African descent entering their house every morning at around 3am.
According to the parents, the girls shout: “There she is, there she is,” before hitting out at the walls and screaming loudly.
As a result, the two sisters, aged 23 and 18, are allegedly kept in a small shed with a mattress and a table with a Holy Cross on it.
A cat is also said to be kept inside the shed, locked in a cage after it attacked other family members.
The girls sit on threadbare mattresses stuffed with rue leaves, which are meant to ward off evil spirits.
Their father , who sells bananas to earn money, often brings priests and other ‘healers’ to visit his daughters in an attempt to exorcise them, but so far, nothing has worked.
Neighbours believe the girls are victims of a spell, or have used a Ouija board in the past.
Theologian Luis Riea Jimenez said: “According to what they say they see there is a spiritual entity that is disturbing and changing his personality. They have been affected in their psyche.
“You could say they are being manipulated and therefore try to attack. Schizophrenia is the scientific term for what the Bible calls ‘spirit possession’.