Barring three men, the Scotland Yard on Saturday released on bail the remaining nine persons, including two women, arrested in connection with the attack on 'Operation Blue Star' hero Lt Gen (retd) K S Brar.
The New Scotland Yard in a statement said "three men - aged 33, 34 and 25 - remain in custody. The remaining nine are now bailed to return in November, for pending inquiries".
Three others who were arrested on suspicion of immigration law violations, unconnected with the probe into the attempted murder, were referred to the UK Border Agency, the statement said.
Lt Gen Kuldeep Singh Brar was stabbed in an attack by four unidentified men in Old Quebec Street, near Oxford Street, on Sunday.
Following the attack, Brar was taken to hospital with a neck wound and has since been discharged.
Brar, who had led 'Operation Blue Star' in 1984 to flush out pro-Khalistan militants from the Golden Temple, was on a private visit here when he was attacked by four men, suspected to be Khalistan sympathisers.
He suffered a wound on his neck and cheek but his wife was not injured in the attack.
The four men who attacked Brar were described as being of Asian appearance, all with long beards, and were wearing dark clothing and long black jacket.
Brar has since left London and is in Mumbai.
Counter terrorism officers had on Friday arrested eight people in connection with the attempted murder case.
The arrests came a day after officers took into custody three men and one woman on suspicion of conspiracy to murder Brar.