Paris (CNN) -- The mayor of a French town where students were held hostage for more than four hours Monday wants to reassure parents that "schools in France are safe."

"We do not want to create an environment of terror in the classroom," Mayor Jean-Louis Fousseret said. "We shouldn't focus on this issue."

About 20 children, aged 4 to 6, were in a classroom when the incident began; five children and their teacher were held until the incident was resolved, Besancon police said.

The hostage-taker is about 17 years old, according to the French Ministry of Education. He was armed with two swords and had "demands," the ministry said, without specifying what they were.

He has been arrested, the mayor said.

"We were dealing with someone who was suicidal and wanted us to give him a weapon," Fousseret said. "There is no specific danger in Besancon."

The father of one of the hostages said that he was "very afraid" for his child but that the students had confidence in their teacher.

"The teacher was very, very calm and confident. She helped them," Babacar Kebe told BFM. "I have not asked them questions because they are very young, and I don't want them to get upset."

A security cordon was placed around the school, and police marksmen took positions outside, pictures from the scene showed. They did not enter the school during the incident, the mayor said.

The incident started at 8:30 a.m. at the Charles Fourier school in the borough of Planoise and ended about four and a half hours later.

France last had a high-profile school hostage incident 17 years ago.

Six girls and their teacher were held hostage for two days in the suburbs of Paris in 1993.

A man calling himself "the Human Bomb" strapped explosives to his body and demanded about $18 million to release them.

He was killed by police marksmen using guns with silencers, press reports said.

CNN's Nina Dos Santos, Isa Soares, Vicky Bennett and Alex Mohacs contributed to this report.