Philippine presidential candidates began their campaign early Tuesday with a caravan, topped by areas where they will speak as they remain mindful of restrictions set by the Commission on Elections (Comelec) due to COVID-19.

''The caravan is one of the new things we will see. This ensures that contact between the candidate and people are kept to a minimum,'' said Alan German of Agents International in a phone interview Tuesday.

Health Secretary Francisco Duque III, in a radio interview, appealed to the candidates '' to initiate having orderly and compliant rallies, with proper distancing, wearing of face masks, frequent handwashing and sanitation."

"This is my appeal to our candidates. They should carry the message of health concern to the people," he added.

Incidents of alleged violations of campaign rules and safety protocols marred the first day of the campaign period for national candidates in the May 9 polls, according to the Commission on Elections (Comelec).

In a virtual press briefing, Comelec spokesman James Jimenez said they have received unofficial reports of alleged campaign violations by still unnamed candidates.

"We have not received any untoward reports although, there have already been reports of some potential violations of certain election norms and practices," said Jimenez.

Among them, he said, are reports of campaign activities, where participants are not wearing face shields and not observing physical distancing.

He also pointed at a report via social media of a campaign, where a government-owned vehicle was supposedly used by a candidate.

Former Senator Ferdinand Marcos Jr and Davao City Vice Mayor Sara Duterte Carpio started their campaign with a grand rally at the Philippine Arena in Bulacan Tuesday evening.

Vice President Leni Robredo and Senator Francis Pangilinan began their trek in Naga City. And Manila Mayor Francisco ''Isko Moreno'' Domagoso and Willie Ong went on a caravan around the city, capped with a rally at the Kartilya ng Katipunan near City Hall.

Robredo rallied the people to join her in changing the kind of politics that has deprived Filipinos from having better lives.

Duterte-Carpio embarked on a long caravan from Davao to Bicol last weekend while Domagoso and Ong were in Manila.

Senator Ping Lacson and Senate President Vicente Sotto III were in Cavite while Senator Manny Pacquiao and Congressman Lito Atienza were in General Santos.

Informal surveys place Marcos in the 50 percent mark while Robredo is a little above 15 percent with 90 days left in the contest.

But Robredo, who began with one percent awareness in 2015, uncorked a big rally to catch up with Marcos in the 2016 vice presidential race. Robredo won the vice presidency over Marcos.

Marcos' lead appears formidable in his rematch with Robredo but history could be against him. ''The only early leader who won was Joseph Estrada for the 1998 national elections,'' said German. DMS