The brother of a Briton slain in a family shooting in the French Alps presented himself to police to deny any involvement in the bloody attack that investigators remain at a loss to explain, a prosecutor said yesterday.

Eric Maillaud said Saad al-Hilli’s brother initially contacted British police after news of the attack, in which four people died, to seek confirmation of what had happened.

He went back after reports emerged suggesting that a fraternal dispute over family finances may have had something to do with it.

“The brother spontaneously presented himself to the British authorities, at first because he was worried and wanted to know if it was true that his brother had died in France,” Maillaud said.

“He went back again today and told them: I have no conflict with my brother.”

Maillaud had earlier said that British police had told French authorities of a financial dispute between the murdered British man and his brother but cautioned against jumping to the conclusion that it could be linked to Wednesday’s attack.

The prosecutor also revealed that al-Hilli, who was shot dead on Wednesday along with his wife, mother-in-law and a passing French cyclist, was “totally unknown” to British and French intelligence services, contradicting media reports suggesting he had been placed under surveillance around the time of the last Gulf war.

The prosecutor’s comments appeared to indicate that the hypothesis of a possible family dispute being behind the killing was not being taken seriously, leaving the case as mysterious as it has been since the outset.

Maillaud revealed that Hilli’s four-year-old daughter Zeena, who survived the attack, had not been able to help the investigation beyond confirming the identity of her parents and that she would be returned to England soon.

Maillaud said he did not know when he would be able to talk to Zeena’s seven-year-old sister Zainab, who is in hospital in Grenoble after receiving a bullet wound in the shoulder and a fractured skull in Wednesday’s attack.

The girl is still in a medically induced coma designed to speed her recovery.

“She is still under medical protection. The doctors have absolutely not given a green light for her to be interviewed,” the prosecutor said. “If and when they do, it will happen in the presence of British diplomats.”

The prosecutor underlined how important the girl’s potential testimony may become to a case in which the authorities appear to be rapidly running out of leads.