“Deeply shocked by the horrific attack that took place at Conflans-Saint-Honorine.
We are next to our French friends and the victim's family, ”Borrell wrote on Twitter.
He stressed that hatred and terrorism "will never defeat freedom and democracy."
Earlier, US President Donald Trump and Canadian Foreign Minister Francois-Philippe Champagne condemned the murder of a teacher near Paris.
On the evening of October 16, in a suburb of Paris, a young man beheaded a teacher, the attacker was shot dead by the police.
French President Emmanuel Macron called the murder a terrorist attack.
The BFMTV channel, citing sources, reported the arrest of the 11th person as part of the investigation into the murder of a teacher.