After allegedly gunning down an abortion doctor, authorities say James Kopp fled overseas and led a solitary life with the help of allies in New York and elsewhere.

His life as a fugitive came to an end Thursday, when he was arrested outside a post office in Dinan, France.

FBI agent Joel Mercer said Kopp, one of the FBI's most wanted fugitives, was picking up a package from New York containing $300 and may have planned to leave the country. 

State and federal authorities will seek his extradition to the United States, where he faces charges in the October 1998 death of Dr. Barnett Slepian, 52. The Buffalo-area doctor was killed by a sniper's bullet as he heated soup in his kitchen. 

Kopp, 46, known as "Atomic Dog" in anti-abortion circles, is also wanted by Canadian authorities for allegedly wounding an abortion doctor there in 1995. 

Two people described as anti-abortion activists were arrested Thursday for allegedly plotting to hide Kopp in New York City. 

Loretta Claire Marra, 37, and Dennis John Malvasi, 51, were ordered held without bail on charges of conspiring to harbor a felon. A federal complaint alleges they rented an apartment under an alias "as a safe house" for Kopp. 

Malvasi had pleaded guilty in 1987 to dynamiting a New York abortion clinic and planting a bomb that was defused before it exploded at another. FBI agents intercepted a series of cryptic messages the suspects left for Kopp in an e-mail account, the complaint said. Kopp left his own messages asking them to send him enough money to sneak back into the United States through Montreal. 

"The sooner I get about 1000, the sooner you see this smiling cherubic face," Kopp wrote, according to court papers. 

Authorities said other arrests are possible. 

"Mr. Kopp did not leave the country without assistance. He did not remain abroad without assistance," said Hardrick Crawford Jr., acting special agent in charge of the Buffalo FBI office. 

Aware of the worldwide manhunt, Kopp spent a year moving among hostels in Ireland until March 12, when, with police closing in, he moved to France, the FBI said. 

"Mr. Kopp reads the newspapers," Crawford said. "It was getting a little warm in Ireland." 

Kopp, of St. Albans, Vt., became the subject of an international manhunt a month after Slepian's shooting. 

He had used at least 28 aliases and been arrested in more than two dozen places in the United States and Italy for protesting abortion. He was last seen Nov. 3, 1998, the day before authorities issued a warrant in hopes of questioning him. 

Kopp's car was found abandoned at the Newark, N.J., airport a month after the shooting. Authorities have said it was spotted in Slepian's neighborhood in the weeks before the doctor was killed. 

In the months following the shooting, investigators found a scope-equipped rifle buried near the Slepian home, and law enforcement sources said Kopp had been linked, through DNA testing, to a strand of hair also found near where the sniper fired. 

While on the run, Kopp obtained driver's licenses and passports, changed aliases frequently, lost some weight and assumed a more clean-cut appearance, authorities said. Mercer said he believed Kopp had been in Europe for some time. 

Kopp faces state and federal charges of murder and violating the federal Freedom of Access to Clinic Entrances Act by using deadly force against an abortion doctor. Both charges carry up to life in prison. The federal charge can bring the death penalty. 

Canadian authorities issued an arrest warrant for Kopp last year in the attempted murder of Dr. Hugh Short, an abortion doctor shot at his home in Ancaster, Ontario, in 1995. 

Police also want to talk to Kopp about the shootings of a doctor in Vancouver in 1994 and another doctor in Winnipeg in 1997.