(CNN) -- An international judge has resigned from the special court set up in Cambodia to try people accused of committing atrocities under the Khmer Rouge in the 1970s, saying his Cambodian counterpart was obstructing efforts to investigate cases.
The resignation by Laurent Kasper-Ansermet, announced Monday, is the second departure of an international judge from the court in the past six months amid tensions with local officials.
His predecessor, Siegfried Blunk, resigned as international co-investigating judge in October, complaining that statements by Cambodian government ministers about two of the court's cases threatened to undermine proceedings.
Those same two cases, known as Cases 003 and 004, are at the heart of the dispute between Kasper-Ansermet and You Bunleng, the national co-investigating judge for the court.
"Judge You Bunleng's active opposition to investigations into Cases 003 and 004 has led to a dysfunctional situation," Kasper-Ansermet said in a statement attributed to him on the court's website.
Prosecutors for the court filed submissions in September 2009 asking the judges to begin investigating five people, whose names have not been disclosed publicly. The submissions were divided into Cases 003 and 004.
Based on a French concept, the two investigating judges of the court, one international and one Cambodian, are responsible for collecting evidence to decide whether people charged by prosecutors should be brought to trial.
Kasper-Ansermet, a Swiss citizen, said You Bunleng had "constantly contested" his authority to investigate the two cases. He said You Bunleng had refused to discuss the cases with him during an informal meeting and had also issued written orders to him demanding that he immediately cease his "unlawful activity."
Kasper-Ansermet "considers that the present circumstances no longer allow him to properly and freely perform his duties," according to the statement, which said his resignation will take effect May 4.
You Bunleng was not immediately available for comment on the matter.
The tribunal, known as the Extraordinary Chambers in the Courts of Cambodia, began its work in 2007 after a decade of on-and-off negotiations between the United Nations and Cambodia over the structure and functioning of the court.
In 2010, it issued its first verdict, convicting Kaing Guek Eav, commonly known by his alias, Duch, of war crimes, crimes against humanity, murder and torture.
At least 1.7 million people -- nearly a quarter of Cambodia's population -- died under the 1975-1979 Khmer Rouge regime from execution, disease, starvation and overwork, according to the Documentation Center of Cambodia.
Opening statements in the court's second trial, Case 002, began in November. In that trial, four former Khmer Rouge government ministers face charges of crimes against humanity and genocide.