Almost 300 hot spots were detected over Sumatra and Kalimantan yesterday that were due to forest and land fires, and the number is expected to increase in the coming dry months.

The figures were disclosed as news emerged of an interview given by the Singapore envoy in Jakarta, who said the Republic would continue to pursue those responsible for haze-belching forest fires in South-east Asia last year.

"We are going after, to put it starkly, the bad guys that are causing this problem," Mr Anil Kumar Nayar told the Agence France-Presse news agency last week. He said Singapore was not crossing any line in pursuing these companies and was within its rights to enforce its law.

"We are not doing something that is extraordinary. It is not targeting any country or anybody's sovereignty," he added.

His comments came amid tensions between Indonesia and Singapore over the latter's decision to take action against a director of an Indonesian firm linked to last year's regional haze, considered to be one of the worst in recent history.

The crisis affected millions across South-east Asia and caused more than half a million Indonesians to suffer from severe respiratory illnesses. Errant pulp and paper firms have been blamed for the fires.

Satellites yesterday recorded 288 hot spots - 245 hot spots over Sumatra island and 43 over Kalimantan - Indonesia's National Disaster Management Agency spokesman Sutopo Purwo Nugroho said in a statement.

The figure is small compared with about 3,000 at the height of last year's crisis, but he warned that the "potential for fires will increase" in the drier months of July to September. "Dry conditions, scarcity of water and difficulty in accessing the locations will make it hard to douse the fires," he said.

Two helicopters and two air-tractor waterbombers were deployed to spray water from the air in Riau province, which had 26 hot spots. Troops, police and personnel from other agencies are controlling the blazes on the ground, he said. "Most of the hot spots are a result of intentional burning," he said. He did not say who were behind the fires but advised the community not to clear land by setting fires.

Last Friday, major palm oil companies said they have ditched a landmark "zero deforestation" pact, saying the government's recent efforts to strengthen its certification standards were sufficient.

The 2014 Indonesia Palm Oil Pledge, or Ipop, was hailed as one that would boost efforts to fight rampant deforestation, annual forest fires and choking haze.