The man was allegedly held captive and assaulted over three days.

Four people have been charged after a man was allegedly kidnapped.

A man allegedly kidnapped and held captive for three days in South Australia has escaped, with four people now charged.

Police allege the 30-year-old man was held against his will at a property in Angle Park, northwest of Adelaide, between February 2 and 4.

He was allegedly assaulted several times by multiple suspects before managing to escape.

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The man sought help from members of the public, who contacted police.

Police said he did not suffer serious physical injuries during the ordeal.

Three men were arrested several days after the incident — a 41-year-old from Angle Park, a 22-year-old from Woodville Gardens and a 26-year-old from Parafield Gardens.

They were charged with serious offences including unlawful detention and aggravated assault, and remain in custody.

A 28-year-old woman was also arrested at a pub in Nuriootpa on Thursday following further investigations.

Police said the woman, who has no fixed address, was the fourth and final suspect.

She was also wanted for 20 counts of theft allegedly committed at various locations across the metropolitan area.

The woman has been charged with offences including abduction and assault, and was refused police bail to appear in Elizabeth Magistrates Court on Friday.

“Police wish to reassure the public that all parties involved in this incident are known to one another,” SA Police said in a statement.