A Harvard senior's chance encounter on an evangelical mission over spring break led to the FBI's arrest of three suspected kidnappers, ending a four-day, nationwide search for two sisters who had been abducted from their Michigan home.

Theresa M. Hainer, 9, and Jessica L. Hainer, 6, were returned to their Galesburg, Mich., home Tuesday night after police in Daytona Beach, Fla., apprehended three men, one of them the girls' former babysitter.

The police were tipped off by Loh-Sze Y. Leung '97, a Dunster House resident, who met the men and the girls last Monday and later saw them on television.

The next morning, police arrested Ronald S. Stafford, 21; his brother Lee Stafford, 17; and Rick J. Geer, 19, on federal kidnapping charges. FBI agents testified last week that at least one of the girls had been sexually molested.

The girls had last been seen in the vicinity of their home in Galesburg, Mich., on Friday, March 21 in the company of the three men, the FBI said. Their disappearance triggered a nationwide search for the men, who the FBI described as armed and dangerous.

"I believe it was God that led me to meet them, to place me in the same area of the beach at the same time and lead us to have a conversation, and led them to be so open with us," Leung said in an interview yesterday. "It's got to be divine."

Leung was in Florida with students from M.I.T., Wellesley and several Minnesota colleges as part of the InterVarsity Christian Fellowship's annual Florida Evangelism Project, whose participants talk with people in Daytona Beach--many of them college students on spring break--about Christianity and "seek to show God's love to people in tangible ways," she said.

Leung was swimming Monday afternoon when she met Lee Stafford, who told her that he was 18 and that he had recently earned his GED. Lee Stafford pointed out his brother and his friend in the water and said they were with two girls who he said were his brother's children.

"He was completely honest with me and told me everything about himself," said Leung. Later, Leung and two friends from MIT were introduced to the two girls.

"They were really quiet and withdrawn," Leung said. "The older one seemed kind of unhappy. They looked dirty because they had been swimming in the ocean all day. It struck us as kind of odd."

Over a dinner of spaghetti and hamburgers that night in the students' hotel room, the men discussed religion with Leung and her friends. The men left with Theresa and Jessica around 7:30 p.m.

Leung said she felt sorry for Lee Stafford, who she said "seemed kind of unhappy." He said he had moved from Michigan to Florida to achieve greater independence from his parents, and spoke of possibly getting a job at a pizza store in Daytona Beach, according to Leung.

"He was looking for adventure and excitement, and independence and freedom, but I couldn't see that he was going to find it by leaving home," Leung said. "None of them fit into the Daytona Beach scene."

After the men left, Leung settled down with other students to watch the Academy Awards ceremony on television. Before the program began, they saw an announcement about the kidnapping, with images of the men and the girls. "All of us recognized them instantly," Leung said.

Karl Wirth '93, a Harvard graduate who works at MIT and was leading the evangelism project, called the police and the FBI.

The students spent the night waiting, praying and filling out witness forms.