Kim Kardashian will testify against a gang of 10 people known as the “grandpa robbers” who are accused of stealing jewelry worth $9 million at gunpoint from her.

Authorities have described them as a seasoned and coordinated criminal group.

Kim Kardashian, testifying in the trial of the burglars accused of tying her up and robbing her at gunpoint nearly nine years ago, told a Paris court on Tuesday that she “absolutely thought” her assai...