Seven persons, allegedly involved in the murder of 'Pottu' Suresh, a DMK functionary and associate of union minister MK Alagiri, surrendered before the judicial magistrate court in Dindigul district on Saturday, police said.
They had murdered Suresh over previous enmity, sources said.
Police said they would file a petition seeking their custody on Monday.
N Suresh Babu alias 'Pottu' Suresh was hacked to death on the night of January 31.