Paris/Cairo: The machete-wielding attacker who was shot by a soldier outside France's Louvre museum refused to answer investigators on Sunday after being formally placed into custody at a hospital, a source at the Paris prosecutor's office said.

Abdullah Reda al-Hamahmy, an Egyptian, was shot several times on Friday after attacking soldiers as he cried "Allahu Akbar" in what French President Francois Hollande described as a terrorist attack.

"The first interview took place this morning, but it turned out to be a short one. For the moment, he refuses to talk to investigators," the source at the prosecutor's office said.

Hamahmy's father told Reuters it was "nonsense" to suggest his son was a terrorist, saying that the youngest of four children was a law graduate who had been working in the UAE for about five years and was in Paris on business.

The 29-year-old arrived in France on January 26 after obtaining a tourist visa in Dubai. Egyptian security officials have not said whether he had any known links to militant groups.

Hours before the Louvre attack, an entry on Hamahmy's Twitter account was posted reading: "Why are they afraid of the establishment of an Islamic state? Because the country of Islam will defend its resources and territory and the honour and dignity of Muslims."

Reuters could not independently verify the authenticity of the tweet and the account has since been shut down.

The incident underlined the Islamist militant threat facing France, which is still under a state of emergency as presidential elections loom following a series of attacks over the past two years that have killed more than 230 people.

Hamahmy's father, Reda Al Refaai, in an interview on Saturday accused French officials of fabricating the allegations against his son to excuse the force used to stop him.

Asked if his son had shown Islamist militant tendencies, the retired police major general said: "If he had I would have thrown him out of the house."

French investigators are hunting for clues to establish whether he acted alone, on impulse, or on orders from someone. He attacked troops checking bags near the museum's shopping mall with a machete in each hand, wounding one soldier.

Hamahmy's father said he last spoke to his son a few hours before the attack and that they had discussed what colour hat Hamahmy should buy to protect him against the cold weather of Paris.

He said he heard the news of the Louvre incident via Facebook. Shortly afterwards, police came to his house to ask some questions before leaving.

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