THE HAGUE -- Dutch prosecutors vowed Friday to pursue a probe into murder allegations against Philippine communist leader Jose Maria Sison despite the courts saying the case was closed two months ago.

Sison, 68, the founding chairman of the Communist Party of the Philippines and its military wing, the New People's Army (NPA), has been living in the Netherlands since 1987.

"Today, the public prosecution service sent a notice of further prosecution" over the Sison allegations, read a statement from the Dutch prosecutors' office.

Wim de Bruin, spokesman for The Netherlands’ Public Prosecution Service, told INQUIRER.net in a phone interview that Sison will no longer be detained while the criminal investigation is underway.

“The investigation is expected to be completed by the middle of the year, this summer, after which Mr. Sison will again be asked to appear before the court,” he said.

Sison was arrested in August 2007 in the town of Utrecht where he lives, on suspicion of having ordered, from the Netherlands, the murder of former NPA commanders Romulo Kintanar and Arturo Tabara.

Kintanar was killed on January 23, 2003 and Tabara on September 26, 2004. Both men, who belonged to Sison's inner circle, were victims of what the Philippine military says was an internal purge of the NPA.

Sison, known also as Armando Liwanag, lives in self-imposed exile in the Netherlands. His request for political asylum was rejected but the Dutch government has not expelled him because his life is deemed to be in danger in the Philippines.

De Bruin said Sison has been notified about his further prosecution.

The prosecutor said the earlier investigation by the International Crimes Team of the National Criminal Investigation Department was deemed insufficient.

“The reason for the decision is the investigation by the police is not yet finished and would take a few more months,” he said.

The District Court in The Hague ordered in September the release of Sison, a decision the Court of Appeals upheld. In November 2007, the examining magistrate closed the preliminary inquiry.

Asked if there are plans to come to the Philippines to gather evidence, De Bruin said: “I can't tell you.”