"Several fighter jets were seen flying over Felda Sahabat at about 8:35 am Thursday," online newspaper The Star reported.
The report added that the aircraft are believed to be heading towards the villages of Tanduao and Tanjung Batu in Lahud Datu, where the group led by Raja Muda Kiram is holed up.
Malaysian police on Wednesday claimed to have recovered the bodies of 13 Filipinos during their search operation after the Tuesday assault on the standoff site in Sabah.
The security forces initially said they had defeated the so-called "Royal Sulu Army," but later admitted most of the gunmen had escaped.
AFP PHOTO / MOHD RASFAN
Kiram's supporters arrested
Dozens of supporters of the Filipinos engaged in a standoff were arrested for questioning by Malaysian police, local media also reported on Thursday.
The detainees, all of which were appended overnight, include a relative of standoff leader Raja Muda Kiram and a Sabah politician.
The Kiram relative, according to The Star, could be either Raja Muda's son or one of his top commanders, a former National Moro Liberation Front (MNLF) combatant who married into the family.
This person is a "very close relative" of the standoff leader "who had played an advisory role to the Sulu group [and] has gone into hiding either [in Lahud Datu] or in Semporna," the report added.
Scores of MNLF veterans are on their way to Sabah to fight for self-proclaimed Sulu Sultan Jamalul Kiram III, a guerrilla leader announced on Wednesday. – with reports from Carlos Santamaria/Rappler.com