Trump tweeted Saturday that Democrats are at fault for the deaths of two migrant children.

The president says Democrats are to blame for the eight-year-old Guatemalan boy who died in Border Patrol custody on Christmas Eve.

President Donald Trump is now blaming Democrats for the deaths of two migrant children who died in federal custody earlier this month.

In his first public comment on the two tragedies Saturday, Trump tied the deaths to the political impasse over funding for the federal government, saying in a series of tweets that Democrats are to blame for refusing his $5-billion pet project to build new walls along the southern border.

The two young children died in Border Patrol custody over the span of just a few weeks. The latest was an eight-year-old from Guatemala who died on Christmas Eve. Medical examiners say the boy, Felipe Gomez Alonzo, tested positive for influenza. Weeks earlier, seven-year-old Jakelin Caal Maquin, died of dehydration after being detained in New Mexico with her father.

Trump’s comments come as Department of Homeland Security Sec. Kirstjen Nielsen finishes up a two-day tour of the border to inspect the conditions at processing and detention facilities for migrants in both El Paso, Texas and Yuma, Arizona.

Already Border Patrol has moved to step up medical screenings for children since the two deaths.

And amid the growing scrutiny, CBP has also shifted its policy of holding families until Immigration and Customs Enforcement takes over custody, as Vox’s Dara Lind reports. The new plan allows agents at the border to release families directly if they’ve been held for more than a few days, which could leave hundreds of families dropped around El Paso and around the Rio Grande Valley.

Deaths along the border have been a problem for a long time

The tragedy of the two children’s deaths only amplifies what has been true along the border for a long time: The journeys that families take are often extremely dangerous, and deaths along the border are not at all uncommon.

By official counts, more than 7,000 migrants have died trying to cross the southwest border since 1998, but it’s likely those statistics are dramatically lower than the reality.

And for years, advocates have complained of the conditions at Border Patrol facilities, where they say migrants are forced into excessively cold holding cells. In the last year alone, six adults have died in Border Patrol custody, the Washington Post report.

But as Lind notes, the two children’s deaths are the latest signal that the immigration system isn’t designed to deal with families crossing into the US:

That goes double for Customs and Border Protection, which oversees Border Patrol as well as ports of entry. CBP Commissioner Kevin McAleenan told the Senate Judiciary Committee earlier this month that “the infrastructure is not compatible with the reality” of who is getting apprehended — essentially admitting that his agency was ill-equipped to take care of the people currently entering the US.

Administration officials, as well as the president’s allies, have meanwhile tried to spin the sting of deaths as fairly a rare occurrence. DHS counters that before the two migrant deaths this month, no child has died in Border Patrol custody in nearly a decade. On Fox News Friday, Rep. Peter King (R-NY) went as far as praising ICE for its treatment of immigrants.

”These are the only two children that have died, certainly in recent memory,” he said. “Considering what does happen in housing projects … I think ICE has an excellent record.”