The Philippine National Police (PNP) on Wednesday said it now has two "persons of interest" (POI) in the fatal shooting of an American marine scientist and the alleged sexual assault of his Filipino partner in Sibulan, Negros Oriental.

Negros Oriental Police director, Police Col. Timmar Alam, said the 34-year-old woman, who was the partner of Kent Carpenter, 73, is considered a POI, along with her sibling, who has been frequently visiting the couple's house.

“May POI na tayo, two na ‘yung POI natin but hopefully, they can help us pinpoint ‘yung mga suspects na nakita natin (the live-in partner). Sa ngayon, she is still considered as POI and ‘yung isang POI ay ‘yung kapatid nung babae. Siya ‘yung isa sa madalas na nakakapunta doon sa bahay (We already have a POI, we have two POIs, but hopefully they can help us pinpoint the suspects we saw (the live-in partner). For now, she is still considered a POI and the other POI is the woman's brother. He is the one who often goes to the house),” Alam told reporters in Camp Crame, Quezon City during a phone interview on Wednesday.

He clarified, however, that there is no evidence at this point linking the sibling directly to the crime.

Based on initial closed-circuit television (CCTV) footage, police believe the attack may not have been meticulously planned.

“’Yung mga galawan ng mga suspects, parang hindi naman siya ganun kaplanado kasi parang nasa mga 20s lang ‘yung mga suspects. Nagkataon lang talaga, parang kung sino ‘yung may opportunity, ‘yun ang papasukin nila (The suspects' actions don't seem to be that planned because the suspects seem to be in their 20s. It was just a coincidence, it seemed like whoever had the opportunity would be the one they go into),” Alam said.

He said investigators noted inconsistencies in the woman's account of the incident.

The foreigner's partner claimed she was sexually assaulted by the suspects, who also took some valuables from their home.

“Unang-una, hindi naman siya sinaktan. At taga-doon din siya, lokal din siya na resident doon. Doon sa claim niya na sinasabi niyang ginapos muna siya ng charger cord, tapos pinadapa siya. Kini-claim niya na she was sexually assaulted. It is still under investigation kasi wala pa po nag-prove (First of all, she wasn't hurt. And she's from there too, she's a local resident there. In her claim, she says that she was first tied with a charger cord, then made to lie down on her stomach. She claims that she was sexually assaulted. It is still under investigation because no one has yet proven it),” Alam said, adding that a vaginal swab examination on the woman yielded negative results.

Investigators also corrected an earlier report that suggested there had been a forcible entry into the victims' home.

Alam said the woman told investigators that she and Carpenter had been living together for about seven years.

Authorities have found no indication yet that the killing was connected to the American national's work as a marine biologist, although investigators continue to examine all possible angles, including his professional activities.

Police said three men wearing bonnets and face coverings forcibly entered the residence of Carpenter at around 11:30 p.m. on Sunday. The suspects allegedly shot Carpenter in the head, killing him on the spot.

The foreigner was a renowned marine scientist known for his research on fish biodiversity. He authored the scientific paper that identified the Verde Island Passage as the "Center of Marine Shore Fish Biodiversity."

He also served as an adjunct professor and associate researcher at Silliman University in Dumaguete City, Negros Oriental, collaborating with the Institute of Environmental and Marine Sciences and the Angelo King Center for Research and Environmental Management. (PNA)