A high school in northern France where a teacher was fatally stabbed has been evacuated following a bomb alert.

Friday’s attack, which prompted the government to put France on its highest security alert, came as a “jihadist atmosphere” had developed, Interior Minister Gerald Darmanin said over the weekend.

His comments followed the deadly Hamas attack on Israel that unleashed retaliatory measures and air strikes.

There were no classes scheduled on Monday at the Lycee Gambetta high school in Arras, but its doors were open for pupils and staff to pay tribute to teacher Dominique Bernard.

Bernard was killed by a 20-year-old man in an attack that President Emmanuel Macron condemned as “barbaric Islamic terrorism”.

Macron posted a message on social media platform X, formerly Twitter, to pupils and school staff earlier on Monday.

“If I’m speaking to you, it is to assure you all that we stand with you,” he wrote.

“We will always counter blind hatred with the inextinguishable thirst to teach. The thirst to learn. The thirst to live freely”.

On Friday, the attacker, a former pupil whose elder brother was serving time in prison for links to Islamist militant networks, fatally stabbed Bernard and wounded three other people.

After the bomb alert on Monday, teachers, some of them in tears and holding each other, left the building, as did pupils who had come to lay flowers in tribute to Bernard.

As a police bomb squad arrived, teachers and students gathered in the courtyard of a building opposite their school as civil protection personnel comforted them.

A minute of silence is planned for later in the day in schools across the country.