Twitter owner Elon Musk has filed a lawsuit against the owner of the ElonJet account. This account specialized in tracking Musk’s private jet, according to the BBC.

The billionaire noted that the activities of the account, which has been subscribed to by more than half a million users, are a source of danger for his son. The account owner, 20-year-old American Jack Sweeney, tracked the location of Elon Musk’s private jet based on publicly available flight information.

Musk said the car with his son was already becoming the target of stalkers who were watching the vehicle, believing Elon himself was inside. According to Musk, the social network he led will continue to block accounts that track people’s whereabouts in real time because they are a security threat.

Previously, the young man’s account was limited.