MANILA, Philippines – (UPDATE 2) Thousands of protesters marched to the Makati City financial district on Wednesday to express their disgust over the plan of President Gloria Macapagal-Arroyo’s allies in Congress to rewrite the Constitution.

Arroyo’s opponents and former allies, presidential aspirants, and militant groups converged on the intersection of Ayala Avenue and Paseo de Roxas for a three-hour program that ended peacefully at 8 p.m.

The crowd peaked at 6,000, one of the lowest turnouts in the protest hotbed, said Chief Superintendent Jaime Calungsod, head of the Southern Police District (SPD).

But Bagong Alyansang Makabayan (Bayan) secretary general Renato Reyes Jr. said the crowd peaked at between 13,000 to 15,000.

Last week, the House of Representatives passed a resolution that would convene a constituent assembly to amend the 1987 Constitution, renewing fears that Arroyo’s term could be extended beyond 2010.

Former presidents Corazon Aquino and Joseph Estrada rallied the public against Charter change, in statements that were read to the crowd.

"Huwag natin hayaan ang isang walang hiyang pang-aabuso sa ating pinakapayak na batas [Let us not allow this abuse to our fundamental law]," Aquino said in her message, which was read by her grandson Kiko Aquino-Dy.

"Kahit mahina ang aking katawan, matatag ang aking paninindigan laban sa katiwalaan [I may be weak, but my resolve to fight corruption remains strong]," said the former president, who underwent surgery for colon cancer last April.

Aquino said she felt "pain and sadness" because of the government betrayed the public's trust.

"It's painful to see all our gains being eroded," said Aquino, who led a bloddless uprising in 1986 that toppled the Marcos dictatorship and restored democracy in the country.

Estrada said that if the constituent assembly push succeeds, it will be the third time for Arroyo to violate the Constitution.

"Binalewala niya ang Constitution nang manungkulan siya noong 2001 at nuong Hello Garci scandal noong 2004 [She disregarded the Constitution when she assumed power in 2001 and during the Hello Garci scandal in 2004]," said Estrada in a statement read by his son San Juan City Major JV Ejercito.

Estrada was referring to the popular revolt in 2001 that ousted him from power and installed his then vice president, Arroyo, into power; and the leak of wiretapped recordings that showed alleged cheating operations that led to Arroyo's victory in the presidential elections in 2004.

Former Speaker Jose de Venecia, who had a falling out with Arroyo in January 2008 after his son linked her husband to corruption said: "This is illegal. This is unconstitutional. We must continue to fight and mobilize public opinion, we cannot allow this to happen,"

Linggayen-Dagupan Archbishop Oscar Cruz catholic bishops would organize anti-Charter change protests in their districts.

Three potential presidential candidates, Senators Francis Escudero and Manuel Roxas, and Pampanga Governor Ed Panlilio joined the rally.

"Kailangang mag-ingat ang Malakanyang, baka mauwi ito lahat sa rebolusyon [Malacañang must be careful, this could lead to a revolution]," said Lacson.

Similar protests were scheduled in Baguio, Calamba City, Lucena City, Batangas City, Nasugbu, Bacoor, Dasmarinas and Silang Cavite, Antipolo City, Cebu City, Tagbilaran City, Sorsogon, Naga, Legazpi, Bacolod, Iloilo, General Santos City, Iligan, Cagayan de Oro City, Cabadbaran in Agusan del Norte, Agusan del Sur and Surigao City, Reyes said.

"Allowing Arroyo and her cohorts to get away with Cha-cha [Charter change] is consent for the perpetuation of a regime guilty of graft and corruption, political repression, and further impoverishment of millions of Filipinos through its anti-people policies," according to civil group Pagbabago! (People's Change Movement).

The protest against the House-led constituent assembly was also brought online, with a "Cause" like "Stop Con Ass [constituent assembly] Now" (http://apps.facebook.com/causes/293075/46310277?m=646ae194), which gained almost 20,000 supporters as of this posting.

Susan Ople, president of Blas Ople Policy Center said the online cause was a good platform to show "people's indignation against Con Ass" even though its supporters would not be present in the rallies.