French President Nicolas Sarkozy on Tuesday assured Prime Minister Benjamin Netanyahu he is determined to bring to justice the killer of four Jews.

“You can be assured of the total determination of the French authorities that the perpetrator of this cowardly and ignoble act be arrested and judged with all the severity required by the gravity and seriousness of this crime,” Sarkozy wrote in a letter his office released Tuesday.

“I wish to express my sincerest condolences to you and to all the people of Israel,” he wrote.

His letter came after Netanyahu vowed to aid French authorities in bringing the killer to justice.

“I promise that the Israeli government will aid the French government in this task,” Netanyahu added. “We would do it anyway – some of the victims were also Israeli citizens.”

Monday’s attack in Toulouse claimed the lives of 30-year-old Rabbi Jonathan Sandler and his sons Arieh, 5, and Gabriel, 4, as well as seven-year-old girl Miriam Monsonego. The three children were Franco-Israeli citizens.

Israeli officials have arranged for the four victims to be transported to Israel for burial, which is expected Tuesday evening.

Sarkozy, who on Monday denounced the attack as “savagery,” was to be present at the Paris Charles de Gaulle airport for the arrival of the bodies there.

France has launched a massive manhunt for the killer and declared a terror alert across the southwest.

Police, who previously said they are concerned a serial killer is at work after ballistics linked Tuesday’s murders to two previous shootings, believe the attacker may be a neo-nazi.

On March 10, a motorbike-borne gunman shot and killed a paratrooper in Toulous. And last Thursday, a gunman on a motorbike opened fire on three uniformed paratroopers of Arab extraction in Montauban, about 30 miles from Toulouse.

French media reported the paratroopers targeted in the second attack were of Arab origin.