MANILA, AUG. 31 -- Sen. Juan Ponce Enrile, still facing questions about his role in last week's bloody military coup attempt, today blamed President Corazon Aquino's government's "failure in national leadership" for prompting "young and idealistic officers" to try to overthrow her.

Meanwhile, authorities were investigating the possibility that the mutinous troops who rebelled may have established their own "provisional government" somewhere on central Luzon island and were set to wage their own private war against the government and communist insurgents. An unverified statement circulating in Manila said the rebels had formed a "ruling junta" that was calling for new presidential elections.

In another development, the rebel forces appeared to gain some support from cadets at the prestigious Philippine Military Academy north of here. A manifesto by a group claiming to speak for the entire student body expressed sympathy for the rebels' cause, and there were unverified reports of a hunger strike.

In a combative speech before a meeting of Rotary clubs, Enrile, who has been widely suspected of having advance knowledge of the coup plot, said he offered "no apologies to anyone" for his refusal to "defend or to condemn" the soldiers who staged Friday's violent abortive coup. "History and our people will judge them," he said.

But Enrile had harsh words for Aquino, accusing her of presiding over an apparent breakdown in public order. "Last Friday's event, my friends, is only a symptom of our national condition," he said. "This malady arises from a fundamental inability of this government to arrest the gloom and drift in the nation, its lack of statecraft and its unwillingness to carve a sound political direction."

While not specifically defending the mutinous soldiers, Enrile clearly trumpeted their theme. He said the young reform-minded soldiers wanted "a good, clean and efficient government."

"These young and idealistic officers and men of the armed forces need your faith, your confidence and your support," said Enrile, the former defense minister who is still thought to enjoy a wide following in the military.

Enrile was met with sharp questions about why he did not use his influence over "the boys," as he calls them, to stop their revolt. Enrile said he made a personal decision not to become involved.

The coup attempt -- the bloodiest and most serious to face Aquino's 18-month-old government -- was led by the same group of young middle-level officers, mostly Enrile loyalists, who launched the February 1986 revolt that drove president Ferdinand Marcos from power and installed Aquino. Their leader was Col. Gregorio Honasan, who is still at large after escaping last Friday.

A manhunt continued today throughout central Luzon for Honasan and other rebel soldiers still at large, while military officials here barricaded the city periphery with tanks and fresh combat troops from outlying areas in anticipation of a possible new attack.

Meanwhile, the communist National Democratic Front said in a statement that the tension within the military gave an "excellent opportunity {for the insurgency} to flourish," Reuter reported.

There were increasing signs today that hundreds of rebel officers and troops may have eluded capture in the final hours of the revolt by changing into civilian clothing. Some reports today said many officers may have slipped back to their bases to rejoin their old commands.

About 760 rebel troops are being detained here in Manila, but it is believed that up to 2,000 may have been involved in the attacks on the presidential palace, three television stations, the Air Force headquarters and Camp Aguinaldo, headquarters of the armed forces and the Defense Ministry. Hundreds of additional troops revolted throughout the provinces.

With so many troops involved, and the loyalties of others in doubt in those crucial early hours, progovernment military officials had to call for reinforcements from the provinces and were not able to effectively assault the rebel stronghold at Camp Aguinaldo until midafternoon Friday, almost 12 hours after the coup began. Armed Forces Chief of Staff Gen. Fidel Ramos had to rely on the untrained Manila police force to stage the key assault that retook the government television station from the rebel troops.

The coup attempt began with a predawn assault on Malacanang palace in which the president's only son, Benigno Aquino III, was shot and wounded. The fighting claimed more than 30 lives, by most reliable estimates, during 20 hours of what often appeared to be pitched street battles. The majority of those killed and wounded were civilians caught in the cross fire.

Many political analysts today, however, were questioning whether the low number of military casualties might indicate that the soldiers were deliberately avoiding shooting at one another. Some columnists and foreign military analysts suggested that the assault on the rebel stronghold took so long to accomplish because the original units assigned to the attack acted half-heartedly. The assault succeeded when the battle-hardened and staunchly progovernment marines came in.

Meanwhile, authorities were trying to determine the authenticity of a statement issued on behalf of the rebel military leaders claiming they had set up "a provisional government, under a ruling junta" based somewhere on central Luzon.

A one-page, typewritten statement circulating among news agencies and on military bases here said an unspecified number of soldiers led by the Reform the Armed Forces Movement were establishing their provisional government until "the political conditions have been stabilized and until a new, clean and honest presidential election shall have been held." The statement was dated Saturday.

The statement, signed only by "the Ruling Junta," criticized Aquino for showing "extraordinary leniency" toward the communists and for offering autonomy to Moslem rebels and to ethnic minorities in the Cordillera mountain region of northern Luzon. The statement also said "corruption has doubled, if not tripled" under the Aquino government.

Some analysts suggested the statement may have been prepared before the failed coup. But one military officer here, who is a member of the reform movement and has close ties to the coup leaders, said in an interview that he believed the statement was authentic. Local newspapers and television reports, quoting unnamed sources, also said it was authentic.

The officer, who used to be a strategic analyst for the reform movement, said Friday's coup attempt may have been the prelude to a more protracted struggle aimed at destabilizing the Aquino government by setting up military rebel bases in the provinces and narrowing Aquino's "sphere of influence."