Justice Baqar is heading the one-man judicial probe formed to inquire into the Model Town incident in Lahore.
According to sources, three high court judges including Justice Ali Baqar Najafi have received threatening letters.
Personnel of the elite force and police commandos were posted outside the court to ensure the judges security.
The law enforcement agencies investigating into the incident.
Lahore High Court Bar has condemned life threats to judges and demanded the government to ensure security of judges and their families.