MANILA - Kilusang Mayo Uno (KMU) organizer and suspected New People's Army (NPA) member Marklen Maga was charged before the Department of Justice (DOJ) Friday for illegal possession of a firearm and ammunition.

CIDG-NCR files additional case of RA10591 or the Comprehensive Firearms and Ammunition Regulation Act against Kilusang Mayo Uno organizer Marklen Maojo Maga. @ABSCBNNews @ANCALERTS pic.twitter.com/5ZGz6hs22U

— Maan Macapagal (@maan_macapagal) February 23, 2018

Maga, son-in-law of jailed National Democratic Front of the Philippines (NDFP) consultant Rafael Baylosis, underwent inquest proceedings, where he opted not to submit a counter-affidavit and other evidence.

Militant groups earlier reported that he was abducted.

WATCH: Alleged NPA member, Marklen Maga, son-in-law of NDF consultant Rafael Baylosis, undergoes inquest proceedings at DOJ for illegal possession of firearm and ammunition pic.twitter.com/2r3u37hCfD

— Ina Reformina (@InaReformina) February 23, 2018

The Philippine National Police Criminal Investigation and Detection Group (PNP-CIDG) said a .45 caliber pistol, a magazine loaded with 7 bullets, and a wallet with several identification cards were recovered from Maga's possession.

He was arrested on the strength of an arrest warrant issued by Cabadbaran City, Agusan del Norte Regional Trial Court Branch 34 Judge Cesar Bordalba for his alleged involvement in the murder of a soldier in March 2017.

On Friday morning, militant groups condemned his alleged abduction and illegal arrest outside Camp Crame in Quezon City.

• Militant groups slam alleged abduction, arrest of KMU organizer

Maga was supposedly abducted by policemen in civilian clothing at a basketball court near their house in San Mateo, Rizal Thursday morning.

His family and lawyers got the confirmation only later that night that he was being held at the PNP-CIDG office at Camp Crame, KMU Secretary-General Jerome Adonis said.

Before becoming a KMU organizer, Maga used to be an active member of the League of Filipino Students. He was also a founding member of the youth group Anakbayan.

He, however, denied being a fighter for the Communist Party of the Philippines (CPP) or its armed wing the New People's Army (NPA).

"Nahuli lang po nila ako sa loob ng subdivision habang naglalaro ng basketball. Napagbintangan lang ako. Mayroon silang ipinapatong sa aking kaso...Hindi po totoo 'yon. Hindi po ako miyembro ng CPP-NPA," he said.

Maga denies he's a member of the CPP-NPA. @ABSCBNNews @ANCALERTS pic.twitter.com/UtA6nCl6Jf

— Maan Macapagal (@maan_macapagal) February 23, 2018

Baylosis, Maga's father-in-law, was rearrested earlier this month for illegal possession of firearms and explosives. He was released in 2016 to participate in the communist movement's peace talks with the government, which have since collapsed.

• NDFP consultant rearrested in QC
• Family, lawyer of arrested NDF negotiator seek justice

-- reports from Ina Reformina, Bianca Dava and Maan Macapagal, ABS-CBN News