Seven Jewish siblings who died in a devastating New York house fire were laid to rest in Jerusalem on Monday at an emotional ceremony attended by several thousand mourners.

Friends and relatives of the Sassoon family attended the service, as well as supporters who only learned of the tragedy through the news. The chief rabbi of Israel and mayor of Jerusalem also paid their respects.

The bodies of the children, ages 5 to 16, were flown to Israel overnight from New York and were immediately taken to Jerusalem in a convoy escorted by police. According to Jewish tradition, funerals take place as soon as possible after death.

"Why seven? Seven beautiful lilies," the children's father, Gabriel Sassoon, cried out in an anguished eulogy. "So pure. So pure."

He recounted how his children enjoyed studying the Torah and other Jewish texts.

"They were such innocent children," he said, his voice choking up. He later called out the names of his children, one by one.

Sassoon described how his wife, although burned, managed to jump out of a second-floor window to try and get help to save her children.

He said he is drawing on his faith for strength.

The children's bodies, wrapped in shrouds, were placed on stretchers for the memorial service, held in a room at Jerusalem's main cemetery packed with scores of mourners. Thousands more stood outside.

Some mourners rocked back and forth in prayer, their cheeks wet with tears, as they listened to the eulogies. Afterward, many in the crowd walked with the family in a procession to bury the bodies.

David Lau, Israel's chief rabbi for Ashkenazi -- or European -- Jews, described the fire as an unspeakable tragedy and urged the family to remain strong. "Each one is a flower in God's garden," he said.

The fire has shattered the ultra-Orthodox Jewish community in the Midwood neighborhood of Brooklyn. Investigators believe it was caused when a hot plate, left on for the Jewish Sabbath, malfunctioned, setting off flames that incinerated the stairs of their home, trapping the children in their second-floor bedrooms as they slept.

The blaze killed three girls and four boys. Both the mother and a daughter -- Gayle Sassoon and 14-year-old Siporah Sassoon -- remain in critical condition. New York fire officials have described the blaze as the city's worst house fire in recent memory.

The tragedy had some reconsidering the practice of keeping hot plates on for the Sabbath, a common modern method of obeying tradition prohibiting the use of fire on the holy day.

Israeli media have said the family lived in Jerusalem before moving to New York two years ago. The tragedy dominated Israeli newscasts.

Alon Edri, who identified himself as a rabbi and relative of the family, said it was significant for them to be buried in the Holy Land.

"We believe that being buried in Israel is important because all of your sins are then absolved," he said.