The US State Department confirmed one American citizen was killed at Holey Artisan Bakery, but did not give any further details.
The incident at the café in the vicinity of the US Embassy left 20 civilians and six gunmen dead on Friday.
Tarishi Jain, a 19-year-old sophomore at the University of California Berkeley, Abinta Kabir, an 18-year-old US citizen from Florida, and Faraaz Hossain - both students at Atlanta's Emory University - were killed during the 12-hour standoff.
Kabir was a sophomore at Emory's campus in Oxford, Georgia, the school said. She was in Dhaka visiting family and friends.
Emory University said in a statement that “the Emory community mourns this tragic and senseless loss of two members of our university family. Our thoughts and prayers go out on behalf of Faraaz and Abinta and their families and friends for strength and peace at this unspeakably sad time.”
Jain of India “was a smart and ambitious young woman with a big heart. Our deepest condolences to her family, friends and the entire Berkeley community,” said Sanchita Saxena, executive director of the Institute for South Asia Studies.
The White House condemned the attack, saying, “We remain in contact with Bangladeshi authorities and have offered any assistance necessary.”
The Daesh terror group claimed responsibility for the attack. It posted photos of what it said were dead foreigners killed in the assault.
In recent months, Daesh and al-Qaeda have claimed several deadly attacks mainly targeting secular bloggers, academics and members of religious minorities, including Shia Muslims, Hindus and Christians.
However, Dhaka denies that Daesh is active in Bangladesh and blames opposition parties or local militant groups for the killings.