CAMP VICENTE LIM, Laguna – A labor organizer suspected of being one of the 72 Southern Tagalog militants facing charges in connection with an alleged ambush by communist rebels in March 2006 was arrested early Sunday, an official of a militant labor group said on Monday.

Leonardo Arceta, 51, was arrested at around 2 a.m. Sunday inside a friend's house in Westdrive Subdivision, Barangay (village) Labas, Sta. Rosa City, by around 10 policemen, said Hermie Marasigan, executive vice-president of the Organized Labor Association in Line Industries and Agriculture-Kilusang Mayo Uno (Olalia-KMU).

Arceta was arrested along with Jessa Brillon, house owner, and her 5-year-old daughter, but Brillon and the child were released two hours later while Arceta remained in detention at Camp Vicente Lim, added Marasigan.

Superintendent Josemarte Paras, Calabarzon regional police public information chief, confirmed Arceta's arrest but did not give details, only saying that an investigation was ongoing.

Arceta's brother Rudy, 49, who immediately went to the camp to verify the arrest, said it was an illegal arrest since the name on the arrest warrant and list of the so-called Southern Tagalog 72 said "Rey Arceta."

"That's not him," he said, insisting that his brother was Leonardo and that the arrest warrant was "misguided."

"We just want to see and talk to him for us to have peace of mind. We want to know where they will take him," Rudy said.

In a statement, Marasigan said Arceta was a legitimate organizer of Olalia-KMU.

Arceta was the eighth militant leader arrested for the alleged 2006 ambush of police by suspected rebels in Mindoro Oriental.

Others in the list of ST 72 included Remigio Saladero Jr., chief legal counsel of the KMU, who has been detained since October 23 last year.

The 72 are facing charges of multiple murder and multiple frustrated murder in connection with the ambush.