Paris stabbing attack leaves two dead and one seriously wounded before police shoot suspect

Isis claim responsibility after man kills mother and sister but investigators believe family dispute may have led to stabbings

A knifeman has stabbed to death his mother and sister and seriously injured a third woman in an attack in the Paris suburb of Trappes.

Police said the attacker, a 36-year-old previously flagged to French authorities as a suspected extremist, was shot dead by officers after taking refuge in a house following the killings.

Isis quickly claimed responsibility for the attack, providing no evidence, but authorities said the motive was unclear and they were not immediately treating it as terrorism.

The terror group described the man as “an Islamic State fighter,” in a statement issued through its Aamaq news agency before it had emerged the two of victims were his relatives.

Police said the surviving victim, who was taken to hospital in a critical condition, was a passer-by.

Local media reported that the knifeman had shouted “Allahu Akbar” before being shot dead in rue Camille Claudel at 10am local time (9am BST) on Thursday. Police opened fire after he ignored warnings as he emerged from the house where he took refuge, officials said.

An Interior ministry source said investigators were looking into whether a family dispute led to the killings. Counterterrorism officials have yet to be asked to join the investigation.

“The reason behind the attack and his profile are not known yet and are being looked into,” a police source added.

Gerard Collomb, France’s interior minister, said the knifeman appeared to have "serious psychiatric problems".

"He was known [to police] for advocating terrorism but it seems he was a disturbed person rather than someone who could respond to calls for action from terrorist organisations like Daesh," he told reporters at the scene.

Earlier he tweeted: ”My first thoughts go to the victims and their loved ones.

“I want to salute the responsiveness and exemplary mobilisation of our forces of law and order. They are already investigating the circumstances of this tragedy.”

Isis claimed the attack was motivated by its leader Abu Bakr al-Baghdadi's call hours earlier for supporters to attack civilians in countries which are at war with the terror group.

Police officials confirmed the Trappes knifeman was listed in a government database of suspected religious and political extremists, but said the attack was not initially being treated as terrorism.

Trappes is a relatively deprived suburb in the west of the French capital with a population of about 30,000. It is situated only a short drive from the wealthy suburb of Versailles, home of the world-famous palace.

Dozens of radicalised youths from the district, which has a large Muslim population, have previously travelled to join extremist fighters in Syria.