Radical preacher Amritpal Singh's close aide Papalpreet Singh has been arrested from Punjab's Hoshiarpur, police said on Monday.
Papalpreet was arrested in a Punjab Police operation that also involved its counter intelligence wing, they said.
Papalpreet is considered to be his mentor and has allegedly been in contact with Pakistan's ISI.
Amritpal and Papalpreet had been on the run since March 18 when the Punjab Police launched a crackdown against the Khalistan sympathiser and his aides.
The radical preacher escaped the police net in Jalandhar district on March 18, switching vehicles and changing appearances.
He and his associates have been booked under several criminal cases related to spreading disharmony among classes, attempt to murder, attack on police personnel and creating obstructions in the lawful discharge of duty by public servants.