MANILA - President Rodrigo Duterte has threatened to place the Philippines under a martial law-like lockdown, as he expressed his frustration that more and more people were ignoring restrictions put in place to slow the spread of the coronavirus.

"I am just asking for your discipline. If you don't want to, the military and police can take over. I am ordering them now to be ready," Mr Duterte said in one of his late-night addresses on Thursday (April 16).

He said should the sweeping lockdown he had ordered start to fall apart before its end date of April 30, security forces could step in to enforce social distancing and stay-at-home guidelines.

"This will be like martial law. You choose," he warned.

He issued his sternest warning yet, as he received word that some districts in metropolitan Manila were already holding boxing matches and cockfighting derbies despite the "enhanced community quarantine" he put in place in March.

People had also been spotted binge drinking along alleyways.

Mr Duterte said he had seen big crowds in public markets, and cars causing traffic jams along major roads.

Manila Mayor Isko Moreno earlier shut for 24 hours the borders of a district with a population of over 40,000 after he saw a video on Facebook of some 100 residents there huddled shoulder to shoulder for an amateur boxing match.

Mr Moreno said he also learned that bingo games were being organised in this district.

A thick crowd, meanwhile, was seen walking just inches apart at a public market at another district in Manila, flouting social distancing rules that required them to be at least six feet apart. Many were not wearing face masks as they haggled with vendors.

Motor vehicles clogged a major highway leading to Manila, as thousands of motorists began hitting the road although movement had been restricted to essential travel, such as making grocery runs or for medical emergencies.

A task force overseeing efforts to fight the coronavirus pandemic had reported that at least 100,000 had either been warned, arrested or fined for defying quarantine protocols.

Mr Duterte last week extended a month-long lockdown over Luzon island, which makes up the northern third of the Philippines and half the country's population, till the end of April as the coronavirus continued to spread across the Philippines.

The number of confirmed cases of Covid-19, the disease the virus causes, in the Philippines rose to 5,660 on Thursday, the highest in South-east Asia. At least 362 have died.

Luzon has been effectively shut off from the rest of the Philippines and the world since mid-March. Capital city Manila is in Luzon.

All domestic flights and sea travel, except for those transporting essential goods, have been suspended.

Companies in Manila and the rest of Luzon have wound down and sent their workers home, except for those providing food, medicine and utilities, and banks, telcos and logistics firms.

A web of checkpoints and barricades manned by the military and police across Luzon is making sure everyone stays put.

Mr Duterte asked Filipinos to be more patient, as the government tries to find ways to ease the lockdown without causing a runaway virus outbreak.

"Just hold on a little more," he said.

"I know you're all eager (for the lockdown to end). I am too. I haven't been able to go home to Davao (city) to attend the birthdays of my grandson, partner and son," he said.

"But in times like these, we have to obey the law," he added.