On Monday, a would-be suicide bomber caused injuries to himself and three others when he set off a pipe bomb near New York City’s Port Authority bus terminal. That afternoon, a Department of Homeland Security (DHS) spokesperson confirmed the terrorist had entered the country using chain migration policies. Trump also pointed to chain migration in official remarks.

“Today’s terror suspect entered our country through extended-family chain migration, which is incompatible with national security,” the president declared. “My Executive action to restrict the entry of certain nationals from eight countries, which the Supreme Court recently allowed to take effect, is just one step forward in securing our immigration system. Congress must end chain migration.”

Chain migration refers to the process through which people from the same town or area migrate to a new place.

Trump’s statement came a few hours after DHS Acting Press Secretary Tyler Q. Houlton confirmed that 27-year-old Akayed Ullah, the Bangladeshi terrorist who was reportedly inspired by ISIS attacks on Christmas markets in Europe, benefitted from the chain migration program.

DHS “can confirm that the suspect benefited from extended family chain migration. The chain was initiated by the suspect’s relative who became a U.S. Citizen after entering the country via a visa lottery program,” Houlton announced on Twitter.

.@DHSgov can confirm that the suspect benefited from extended family chain migration. The chain was initiated by the suspect’s relative who became a U.S. Citizen after entering the country via a visa lottery program. (1/2) — Heather Swift, DHS spokesperson (@SpoxDHS) December 11, 2017

Houlton added, “The suspect is originally from Bangladesh and entered the U.S. in 2011 receiving a green card under the fourth family based preference. The Administration has advocated for ending both Chain Migration and the current Diversity Visa lottery program.”

White House Press Secretary Sarah Huckabee Sanders explained that Ullah entered the U.S. in 2011 with an F-43 family immigrant visa.

The New York Post reported Trump’s remarks, but failed to mention the DHS assessment that chain migration enabled Ullah to enter the country.

“Congress must also act on my Administration’s other proposals to enhance domestic security, including increasing the number of Immigration and Customs Enforcement officers, enhancing the arrest and detention authorities for immigration officers, and ending fraud and abuse in our immigration system,” Trump added.

“The terrible harm that this flawed system inflicts on America’s security and economy has long been clear. I am determined to improve our immigration system to put our country and our people first,” the president concluded.

ISIS followers have warned that more attacks are coming. Authorities have noted that Ullah chose the location of his terror attack based on Christmas posters nearby. He also said he was inspired by previous attacks on Christmas markets in Europe. His makeshift pipe bomb even used a broken Christmas tree light as an igniter.

Sanders attacked Democrats in Congress for failing “to take action in some places where we feel we could have prevented this.” She also specifically mentioned chain migration, noting that Trump’s policy has called for an end to the practice. “If that had been in place that would have prevented this individual from coming to the United States.”