An aunt of the Boston Marathon bombing suspects has said the older brother recently became a devout Muslim who prayed five times a day.

Maret Tsarnaeva told reporters at her home in Toronto, Canada, that her brother, Anzor Tsarnaev, had high expectations for his sons, especially 26-year-old Tamerlan.

She said her brother was desperate when he found out that Tamerlan had dropped out of his university.

She said Tamerlan was married and had a daughter in the US.

She called him and his brother, Dzhokhar, smart and athletic, and said she wants proof that they are involved in the bombing.

"Within the family, everything was perfect," she said.