The Amaq News Agency, which is linked to the Islamic State group, reported that a member of the militant group had carried out the knife attack in Trappes, according to SITE Intelligence Group, which tracks the group’s propaganda online.

But Interior Minister Gérard Collomb said the assailant “is more someone unstable rather than someone who would be following the instructions of terrorist organizations.” He described the attacker as having “important psychiatric problems.”

The attack took place in a residential area of Trappes, a working-class and ethnically diverse suburb southwest of Paris.

Collomb told reporters in Trappes that the victims were the mother and the sister of the assailant, and that the attacker had been on a terrorism watch list.

The attacker killed his sister and wounded another person, who was not a relative, on the street where his mother lived, and then entered his mother’s house and killed her there, Collomb said.

He praised the response of police, who were alerted at 9:30 a.m., and called the attack a “tragedy.”

Trappes, a town southwest of Paris that has a reputation for insecurity and violence, has been plagued by unemployment — 20 percent, more than twice the national average. It has a large Muslim population, and it has produced soccer player Nicolas Anelka and popular comedian Omar Sy.

There have not been any large-scale attacks in France this year, but terrorism-related knife attacks have become more frequent. In May, a 20-year-old man stabbed five passers-by, one fatally, in a crowded Parisian neighborhood before he was killed by police.

In October, an assailant stabbed two women to death in front of the St.-Charles train station in Marseille.

This article originally appeared in The New York Times.

Elian Peltier © 2018 The New York Times