President Corazon Aquino, who insists on remaining one of millions of Filipinos who commute to work every day, is under mounting pressure to improve her security following a purported assassination plot against her.

The alleged plot, revealed this week when a suspected thief reportedly confessed to police that he was hired to shoot Aquino early last month, is currently under investigation by military authorities. Although some government officials do not take the confession seriously, the news of the purported plot has fueled demands from the public and her administration that Aquino take extra security precautions, a presidential spokesman said.

The spokesman, Rene Saguisag, said Aquino's office at the Malacanang presidential palace has been bombarded with press commentaries and private messages begging her to move her residence to the palace compound or nearby. Up to now she has insisted on keeping a campaign pledge not to live at Malacanang, the opulent residence for 20 years of her deposed predecessor, Ferdinand Marcos.

The result has been a security nightmare as Aquino commutes twice daily between her modest home in the Manila suburb of Quezon City and her office in a guesthouse in the Malacanang compound, which is located in central Manila on the banks of the Pasig River.

"It's really a hassle," Saguisag said. "You stop at every stoplight because of her insistence that traffic rules be obeyed."

According to sources close to the palace, Aquino does most of her commuting in a bulletproof Range Rover formerly used by Marcos' children. She has shunned the more luxurious limousines that have been offered her, but a double wearing Aquino's trademark yellow dress and eyeglasses sometimes rides in another car, the sources said.

The security problems associated with that long drive, which can take up to an hour in heavy traffic, have prompted thousands of citizens to write letters and sign petitions urging her to move, government officials said. Assuming she will not agree to live in the palace itself, parts of which have been turned into a museum to display the Marcoses' lavish lifestyle, proponents of the move are preparing other options. Chief among them are moving to a guesthouse in the Malacanang compound or one of three houses across the street, two of them government properties formerly occupied by Marcos' relatives and one a private house once inhabited by the family of Aquino's late husband, assassinated opposition leader Benigno Aquino Jr.

The alleged assassination plot "helps that campaign" to get Aquino to move, spokesman Saguisag said.

The alleged plot surfaced when Romualdo Mercado, 30, described as a university economics graduate from Aquino's hometown in Tarlac Province, told police after his arrest for robbery Saturday night that he had been hired to assassinate the president for 500,000 pesos (about $25,000). Mercado told police he had approached Aquino as she was seated on a grandstand while attending an open-air mass and rally at the Luneta Park March 2, five days after she assumed power in a military-led popular revolt. Mercado told police he was about to pull a handgun out of his waistband, but got cold feet and left.

The Manila city prosecutor, Jose Flaminiano, who has long had a reputation as a loyal Marcos supporter, was quoted by Manila newspapers as saying Tuesday that during an eight-hour investigation he conducted, Mercado had implicated two senior military officers, including an active-duty general, in the plot. Yesterday, however, Flaminiano denied having said this. The officers were not publicly identified.

Amid the confusion over the alleged plot, Armed Forces Chief of Staff Gen. Fidel Ramos yesterday ordered the acting chief of the Philippine Constabulary, Brig. Gen. Renato de Villa, to form a composite team of investigators to look into the affair.

In other developments, about 40 Communist rebels and 20 commanders accepted Aquino's call for a cease-fire and surrendered Thursday to government troops on the island of Cebu, The Associated Press reported. The rebels turned over some rifles and more than 1,000 rounds of ammunition to Political Affairs Minister Antonio Cuenco and military leaders in Catmon, about 340 miles south of Manila.

[Defense Minister Juan Ponce Enrile, in a television interview, also said that Imelda Marcos and former armed forces chief of staff Gen. Fabian Ver had plotted to seize power if Ferdinand Marcos had died in office.]