Mendoza said Cervantes might have been killed because he had exposed an alleged plot of active and retired police and military men to destabilize the Arroyo administration.
"There are political motives being looked into..." he said.
Col. Victor Corpus, chief of the Intelligence Services of the Armed Forces of the Philippines, also told a media forum at the Westin Philippine Plaza yesterday that military intelligence is looking at the possibility that the murder of Cervantes is linked to a coup plot.
"It could be said," he admitted. "They are crazy people out there who want to established a military junta but such a junta will never succeed."
Corpus said there could also be a connection between the reported coup plot and the cache of explosives seized from the former men of Navy Lt. Senior Grade Don Anthony Miraflor.
Corpus said the powerful explosives were found at the headquarters of the Navy’s disbanded Special Warfare Group, which used to be under Miraflor.
The discovery of the explosives had "weakened" the alleged coup plot, he added.
Corpus said Miraflor is now "restricted to quarters" at the Naval Education and Training Center in Zambales while he is undergoing investigation.
Corpus said "some crazy people" are trying to recruit military officers to join a coup plot against the Arroyo administration.
"Even if they continue with this recruitment, they will never get any support," he said. "Some crazy people recruit from the military but they are not getting any. Many (military officers) are now already cautious about these things. It will never succeed."
However, Corpus also downplayed the possibility of a coup.
"There is no coup," he said. "These are just rumors."
Mendoza said the perpetrators could be floating the angle that the New People’s Army (NPA) was involved in the killing to mislead police investigators.
"The NPA angle could be one of the tactics to mislead investigators," he said.
Cervantes had disclosed to media that some 80 retired and active police and military men met at Puerto Azul in Ternate, Cavite before Christmas, he added.
Mendoza said he will leave it to police investigators to summon Armed Forces Spokesman Brig. Gen. Edilberto Adan so he could shed light on the murder of Cervantes.
Adan had reportedly communicated with Cervantes hours before the former Army lieutenant was gunned down on a sidewalk along Pamplona in Las Piñas, he added.
Mendoza said Adan’s name appeared in several text messages sent to the cellphone of Cervantes on the day that he was killed.
Mendoza said one message allegedly showed Adan answering a text from Cervantes, which asked the Armed Forces spokesman to "ward off negative perceptions against him" after he was dragged into the destabilization efforts against the Arroyo administration.
Investigators led by Southern Police District (SPD) director Chief Superintendent Jose Gutierrez will summon people who had been exchanging text messages with Cervantes, the police chief added.
Superintendent Diosdado Valeroso, co-founder of the Young Officers’ Union (YOU), said he met yesterday with policemen investigating the killing of Cervantes.
"I gave them a letter asking what the summons is for," he said. "Nothing happened. I just came to inquire about the summons. It was nothing."
Chief Superintendent Oscar Catalan, SPD Intelligence and Investigation director, said Valeroso was supposed to meet him at 9:30 a.m. but that he showed up at about noon.
"(Valeroso) said he will be back by next week," he said. "He only came to ask what the interview was all about."
However, Valeroso said "there was no perception" that police investigators are eyeing him as a suspect in the killing of Cervantes.
Catalan was also evasive in discussing with reporters the gist of his meeting with Valeroso, saying that Valeroso would give details of his "relationship" with Cervantes next week.
Earlier, Gutierrez said police would question Valeroso about the YOU.
Police will also look into reports that Cervantes was killed because he had exposed alleged anomalies in the Land Transportation Office. – With reports from Mike Frialde, Jose Aravilla