Manila, Jul 3 (IANS): More than 230 people have been hospitalized due to alleged food poisoning after attending an event on Wednesday held in tribute to former Philippines First Lady Imelda Marcos, who celebrated her 90th birthday on July 2.

Patients were admitted to five different hospitals in Manila, while authorities were analyzing the source of the poisoning, said the acting head of the National Disaster Risk Reduction and Management Council, Bryant Wong.

Wong said they are collaborating with the Philippines Food and Drug Administration to collect samples of the food served at the event which took place at the Ynares Sports Arena in Pasig City, southeast of Manila, Efe news reported.

The celebration, which was attended by some 2,500 supporters of the Marcos family, were served two different menus - one for VIP guests and another for regular guests. The people who fell ill were from the latter category.

Authorities suspect that the source of the poisoning could be the meat in the adobo - a Philippine national dish - or the egg, although bottled water served to the guests will also be analyzed with the results expected after three days.

Senator and Philippine Red Cross (PRC) Chairman Richard Gordon earlier tweeted that "137 patients suffered from vomiting and dizziness due to alleged food poisoning (...) PRC already alerted nearby hospitals for possible patient transport".

Gordon also said that some guests were nauseous after drinking the bottled water distributed at the event.

Marcos turned 90 on Tuesday, although she also celebrated her birthday on Monday with supporters in an event at Rizal Park in Manila. On Sunday, she attended celebrations in Ilocos Norte, in northern Philippines, which has been the political bastion for the Marcos family.

She ended her nine-year tenure as a congresswoman for the region on June 30 and her children - Imee and Bongbong - continue to pursue their political careers with broad popular support.