MANILA, Philippines (AP) – Philippine police have filed a murder complaint against a woodcarver who confessed to beating to death a Peace Corps volunteer and former Brooklyn journalist while she was hiking alone, officials said Monday.

Juan Duntugan has admitted that he bludgeoned to death Julia Campbell, of Fairfax, Va., with a rock in Ifugao province’s Batad village on April 8, regional police chief Raul Gonzales said. She had planned to see the area’s famed mountainside rice terraces.

Philippines police usually file formal complaints based on evidence they have gathered to prosecutors, who then decide whether to file specific charges against a suspect.

Among the evidence submitted by police against Mr. Duntugan, 24, was a signed affidavit in which he claimed to have killed Campbell in a fit of rage when she accidentally bumped into him as he was fuming over a neighborhood spat, Chief Gonzales said.

Chief Gonzales earlier remarked that the killing “was not premeditated” – a key element in murder – but he said Monday that investigators filed a murder complaint because of the ferocity with which Duntugan attacked Campbell.

“If he did not plan to kill her, he should have stopped when she was already wounded and down,” Chief Gonzales told The Associated Press by telephone.

“But no, he hit her repeatedly on the head until she died,” he said.

Ifugao provincial prosecutor Marvin Ngayawan told the AP that he and other prosecutors would evaluate the evidence submitted by police, including the statements of at least six witnesses, then decide whether he could be charged in court with murder or homicide.

Mr. Duntugan told ABS-CBN television, hours before surrendering Friday, that he did not plan to kill Campbell and dismissed speculation that he killed her during an attempted rape or robbery.

He claimed he dropped a bundle of clothes when Campbell bumped him from behind.

“My mind went blank,” Mr. Duntugan said. “I did not know who she was or what she was. I got a rock and I hit her on the head. If I can change my body for hers, I will do it. But that’s not possible. Whatever punishment you will impose on me, I will accept it.”

Mr. Duntugan’s wife had sold Campbell a soft drink before her hike, and a boy has told police that he saw the suspect near a grave that day. Mr. Duntugan went into hiding the next day.

A police autopsy showed that Campbell was killed by multiple blows to the head, and that her arms were injured, indicating she tried to defend herself.

Campbell, 40, had worked as a freelance journalist for The New York Times and other media organizations.

Her death has drawn national attention because of her volunteer work in Legazpi city in the Bicol region, where she last worked as an English teacher, and in nearby Sorsogon province, where she helped launch an ecology awareness campaign.

Chief Gonzales said the killing has tarnished Ifugao, famous among tourists for its panoramic rice terraces and gentle villagers.

“Hopefully we can recover with the passage of time,” he said.

“If this would not be repeated, I’m sure our place would win back the confidence of people,” he said.