Fresh clashes at an Ecuadorian prison, where six inmates were found hanged this week and three young prison service workers were murdered, left at least 12 inmates dead on Friday, prosecutors said Saturday.

“An investigation is underway to identify those responsible for the death of 12 inmates of the coastal zone penitentiary in Guayaquil,” the prosecutor’s office said on Twitter.

Six inmates were found hanged Wednesday in this prison in Guayaquil, a major port city in southwestern Ecuador plagued by drug-trafficking violence.

The next day, three young female workers were murdered outside the prison complex. And on Friday, at least three inmates were injured during gunfights inside the prison.

Ecuador’s prisons have become the scene of repeated deadly clashes between prisoners, against the backdrop of rivalries between criminal groups fighting each other over drug trafficking.

Since February 2021, eight massacres have been recorded in these prisons, with more than 400 inmates dead, many of whom were found dismembered and burned.

A major port on the country’s Pacific coast, Guayaquil has in recent years become the center of drug trafficking in Ecuador, as it lies between Colombia and Peru – the world’s largest producers of cocaine.