What must be done to atone for the sin of theft after repenting from it?

The repentance from theft and similar acts requires absolution from those whose rights have been violated, by returning the ill-gotten gains to them or seeking their forgiveness, based on the hadith: "Whoever has wronged his brother concerning his honor or anything else, let him seek his forgiveness today before there will be no dinar or dirham." Every participant in the theft is accountable for the entire stolen amount. The stolen item or its value must be returned to the victim, or their forgiveness must be sought. The claim made by the companions that the police taking the stolen money does not absolve one's responsibility unless the money is returned to its owner. It is not a condition to inform the owners of the stolen money when returning it.