Trump tweeted Sayfullo Saipov came into the country via the Diversity Visa Lottery, the State Department program that gives out up to 50,000 immigrant visas a year, according to U.S. Citizenship and Immigration Services.
Those eligible for the visa, granting access to people from countries with few immigrants in the U.S., must have been selected for a diversity visa by the Department of State's lottery, have an immigrant visa immediately available and have the right to be in the U.S.
Those who apply must submit biographic information, two passport-style photos, a copy of a birth certificate, a medical examination, a vaccination record and an arrival/departure record.
Most visas are given to people from African nations, The Washington Post has reported.
Saipov, 29, came to America from Uzbekistan in 2010 and lived most recently with his wife and children in the same northern New Jersey city where several 9/11 attack conspirators stayed.
Uzbekistan is a qualified area listed on the 2019 Diversity Immigrant Visa Program.
Rick Hampson contributed to this report.