Dutch prosecutors charged an environmental activist with murder and illegal weapons possession Wednesday in the killing of populist leader Pim Fortuyn. 

The suspect was identified by colleagues as 32-year-old Volkert van der Graaf, an activist with the group Environmental Offensive. He faces up to 20 years in prison if convicted. 

Dutch media, constrained by rules against naming criminal suspects, had identified him only as Volkert van der G. The Dutch legal system does not publicly name defendants. 

Van der Graaf was chased down and caught with a pistol moments after the fatal shooting of Fortuyn, who was campaigning for a seat in parliament on an anti-immigration platform. Police said the alleged gunman apparently acted alone. 

Police said Van der Graaf, who has refused to make a statement, did not have a gun license. 

At a closed initial hearing before an Amsterdam judge, van der Graaf was represented by a lawyer, prosecution spokesman Robert Meulenbroek said. 

A court statement said the magistrate ordered Van der Graff held for 10 days while three other judges reviewed the case and decide whether to keep him in jail. 

Van der Graaf is an animal rights and environmental activist who had peacefully fought industrial animal farming for years in the courts before he was arrested Monday. 

Police said they had no motive for the crime, and said they could not immediately draw a link between the suspect's activism and the shooting of Fortuyn, who was praised by environmental groups for his policies. 

Fortuyn, 54, was shot Monday as he walked to his car after a campaign radio interview. He was to be temporarily interred Friday in a family tomb after a public memorial service in Rotterdam on Thursday. Fortuyn's remains will eventually be buried in Italy, where he had a vacation house. 

Police said they found ammunition at the suspect's home in Harderwijk, about 30 miles east of Amsterdam, that matched shell casings at the crime scene. 

People familiar with the suspect said they were baffled by the shooting. 

"I don't know him as someone who would use violence," Roger Vleugels, who had helped van der Graaf with legal cases, said on Dutch television. Van der Graaf worked on more than 2,000 lawsuits fighting the expansion of industrial animal farming. 

Environmental groups in the Netherlands condemned the killing, fearing they would be associated with the murder. Telephone threats from Fortuyn supporters were received by Greenpeace and other groups. 

"Pim Fortuyn had reasonable views on the bio-industry," Pigs in Need, an animal rights group, said in a statement. "Fortuyn believed that new agricultural policy needed to be animal friendly." 

In a recent book, Fortuyn wrote: "Animal welfare must be a priority and we need to switch to less industrial production methods," according to the group. It renounced Fortuyn's murder as "stupid extremism." 

In a 2-year-old letter published on the Internet, van der Graaf described how he became a vegan, the strictest form of vegetarian, and had worked for various environmental and animal rights groups since he was a teen-ager. 

At Environmental Offensive, he wrote, "my actions don't come much from love for animals. I just have a basic standard: what happens in factory farming is not right," he says. 

On Tuesday, the government decided to go ahead with next week's general elections, though all campaigning was suspended after Fortuyn's death. His party, Pim Fortuyn's List, said the slain candidate's name would remain on its ballot list. 

In Rotterdam, where Fortuyn's upstart party swept more than 35 percent of the vote in local elections less than two months ago, thousands of people laid flowers and lighted candles outside his home. 

Hundreds of supporters of the gay, outspoken politician stood in line for hours to sign a City Hall condolence log. On Tuesday evening, about 30,000 people marched silently through the center of town.