TACLOBAN CITY, Philippines -- Without any witnesses to rely on, government investigators are now banking on a half-million-peso reward for information that could lead to capture of the killer of a regional trial court judge in Samar.

Both Chief Superintendent Abner Cabalquinto, Eastern Visayas police director, and lawyer Antonio Pagatpat, regional director of the National Bureau of Investigation, admitted that investigators have been stumped due to the lack of witnesses who could identify the lone killer of Judge Roberto Navidad.

The gunman shot and killed Navidad while he was inside his vehicle in downtown Calbayog City on January 14.

"We understand why no one is willing to come out to inform us on what they knew about the incident. They are afraid of possible reprisal," Pagatpat said.

But with the reward being offered, they might just get the witnesses who could help them fast track their investigation, he said.

"We just hope that the reward money that we are offering will help us solve the crime," Cabalquinto said.

He said the P500,000 reward money came from "concerned individuals." Cabalquinto, however, declined to identify the donors.

"But they have raised the reward money out of concern," he said, adding that the donors would like to ensure the killing of Judge Navidad would be the last attack on judges.

Chief Justice Reynato Puno has condemned the killing of Navidad, the 15th judge killed since 1999, and urged investigators to solve the murder.

The NBI and PNP are conducting a joint investigation into the murder of Navidad but have so far not established who ordered his murder and who the gunman was.

Pagatpat said the NBI’s investigation is being undertaken by the Judicial Protection Unit, which was created as a result of the killings of judges.

The 69-year-old judge will be buried in his hometown of MacArthur, Eastern Samar, on Saturday.