The mother of a six-year-old girl who has been missing in South Africa for nearly three weeks has been charged with kidnapping and trafficking her daughter.

The development is a shocking twist in a case that has seized the country’s attention and sparked deep anger in the small, poor coastal community where the family lives.

Joslin Smith has still not been found and police renewed calls for “every citizen, every person” to help find her amid fears she may have been taken to a different city or even out of the country.

In the days after Joslin’s disappearance last month, local media reported that neighbours had accused her mother of selling her for just over 1,000 dollars (£781).

The discovery of a child’s discarded clothing near Joslin’s home last weekend heightened emotions.

Her mother, Kelly Smith — whose full name given by prosecutors is Racquel Chantel Smith — has been charged with kidnapping and human trafficking offences along with two men and a woman.

One of the men is Smith’s boyfriend. She claimed she left Joslin with him on February 19 while she went to work.

Joslin was reported missing that day.

The four suspects did not enter a plea in response to the charges and another court hearing was scheduled for next week. They will remain in custody, prosecutors said.

Joslin has not been found despite a major search operation involving police, firefighters, city authorities and specialised sniffer dog units around the family home near Saldanha Bay, about 75 miles north of Cape Town on South Africa’s west coast. The national minister of police visited the area and met Kelly Smith.

Police said child’s clothing had been recovered last weekend near the settlement of small houses and shacks where Joslin lived.

It was sent to a laboratory for forensic examination. Community members who are also involved in the search said the clothing was spattered with blood and a knife was also found.

Prosecutors said in court documents released on Thursday that Kelly Smith and the others conspired to abduct Joslin and intentionally sold, delivered or exchanged her. The suspects face a sentence of life in prison if convicted of the main charge of human trafficking.

The four suspects left the courthouse in Vredenburg, a town near Saldanha Bay, in an armoured police van as a large crowd gathered outside, repeatedly shouting “Justice for Joslin”.

Western Cape province police commissioner Thembisile Patekile told reporters that more arrests could be made but authorities also had to refocus on the search for Joslin.

“At this stage, we do not have a child,” he said. “Our ultimate goal is to find the child. We still want to find that child alive.”

Authorities have given different spellings for the girl’s name. Police identified her as Joslin while prosecutors named her as Joshlin in their documents.