President-elect Donald Trump appeared to blame the Biden administration’s border policies for the vehicular attack that killed 15 people in New Orleans on Wednesday morning, even though authorities have identified the assailant as a native-born U.S. citizen.

“With the Biden ‘Open Border’s Policy’ I said, many times during Rallies, and elsewhere, that Radical Islamic Terrorism, and other forms of violent crime, will become so bad in America that it will become hard to even imagine or believe,” Trump said in a social media post Thursday. “That time has come, only worse than ever imagined.”

The FBI has identified Shamsud-Din Jabbar as the man who drove a truck with an Islamic State flag into a crowd on Bourbon Street early on New Year’s Day. Jabbar, who was killed at the scene, was an Army veteran from Texas and a U.S. citizen.

Although Trump didn’t explicitly say he was referring to the New Orleans attack, the timing of his Thursday post and his mention of “Radical Islamic Terrorism” suggest he was making the connection. The Trump transition team did not immediately respond to a request for comment. President Joe Biden said Wednesday that Jabbar’s attack appeared to have been inspired by ISIS.

In social media posts that appeared related to the attack, Trump sought to blame migrants for crime in the United States, reprising a central theme of his presidential campaign. In one particularly notable episode in September, the Trump campaign and its allies distorted Homeland Security statistics on undocumented immigrants with criminal records, claiming that the migrants entered the country during the Biden administration. In fact, most did not enter during Biden’s White House tenure. The statistics span the past four decades, and many of the migrants in question entered the country during Trump’s first term.

Jabbar was born in the U.S. during President Ronald Reagan’s administration.

There is no evidence that undocumented immigrants commit crimes at a higher rate than U.S. citizens. The vast majority of those arrested at the southern border do not have criminal convictions. Illegal border crossings reached the highest levels ever recorded during the first three years of Biden’s terms, but those numbers have dropped significantly in recent months.

Hours after the New Orleans attack, Trump claimed on social media that “that the criminals coming in are far worse than the criminals we have in our country” and said “our hearts are with all of the innocent victims and their loved ones, including the brave officers of the New Orleans Police Department.”

Trump’s message suggesting a tie between “criminals coming in” and the New Orleans attack took off on social media Wednesday after Fox News reported that the suspect drove a truck with a Texas licence plate across the border in Eagle Pass, Texas, on Dec. 30. The news network later clarified that new reporting revealed that the truck crossed the border on Nov. 16, and the ID of the driver did not appear to be Jabbar’s. Officials have said that Jabbar rented the car he drove into the crowd, a white Ford F-150 Lightning, through Turo, an online marketplace that allows people to rent out their personal vehicles.

In a Fox News interview Thursday morning, Rep. Michael Waltz (R-Fla.), Trump’s incoming national security adviser, brought up the border when asked about how to prevent further attacks.

“We’ve got to take a hard look at our defences, first and foremost, close our border,” Waltz said.

In addition to appearing to blame the attack on the Biden administration’s border policies, Trump also reprised his claim of a weaponized justice system in a social media post early Thursday, and claimed that the United States is a “laughing stock all over the World!”

“This is what happens when you have OPEN BORDERS, with weak, ineffective, and virtually nonexistent leadership,” Trump said. “The DOJ, FBI, and Democrat state and local prosecutors have not done their job. They are incompetent and corrupt, having spent all of their waking hours unlawfully attacking their political opponent, ME.”

— Meryl Kornfield contributed to this report.