Reyes presented Aldrin Galicia, said to be one of the three gunmen in Rosales killing, to the media at Camp Crame yesterday.
The Lucido gang is also engaged in drug trafficking in Metro Manila and Southern Tagalog, Reyes said.
Galicia, along with two companions, was arrested at a police checkpoint in Tanauan City last Wednesday. He yielded a caliber .45 pistol and a baby Armalite.
Reyes said two witnesses have come forward to testify against Galicia. The two other gunmen are still being hunted down.
Rosales was waylaid in Tanauan City by motorcycle-riding men while he was on his way home aboard his Mitsubishi Pajero.
Reyes said Galicia has been linked to at least 16 other killings. Seven of the victims were policemen.
Galicia was also involved in the kidnap-slaying of Gregorio Lanting, chairman of Barangay Pantay Matanda in Tanauan, in September last year, he said.
Rosales widow, Filomena, a lawyer herself, said she is convinced that the police got the right suspect in her husbands killing.
She called on the Department of Justice to speed up the investigation into the killings of eight other judges nationwide.