President Donald Trump is under fire Saturday morning for lashing out on Twitter at the mayor of San Juan, who on Friday raised major concerns about the Trump administration’s slow action and misleading commentary regarding Hurricane Maria relief efforts in Puerto Rico.

In a series of tweets, the president purported that unidentified Democrats had told the Puerto Rican official “you must be nasty to Trump.” He also claimed “the Mayor of San Juan, and others in Puerto Rico” had demonstrated “poor leadership ability.”

The backlash on social media was swift:

Speaking to CNN on Friday, San Juan Mayor Carmen Yulin Cruz had expressed shock at the Trump’s administration claims that Puerto Rico’s recovery from the devastating hurricane is “a good news story,” and made headlines for saying: “When you’re drinking from a creek, it’s not a good news story. When you don’t have food for a baby, it’s not a good news story…. Damnit, this is not a good news story. This is a people-are-dying story,” as Common Dreams reported.

The president and his team have been broadly criticized for the federal government’s slow reaction to the growing humanitarian crisis, with some critics already deeming this Trump’s Hurricane Katrina, in reference to former President George W. Bush’s botched response to the disastrous hurricane that struck the Gulf Coast in 2005.

Currently in Puerto Rico, most the of island has no electricity—which could take up to six months to fully restore—and nearly half of its more than 3 million residents lack clean drinking water. Food and fuel supplies are critically low, and many are warning that Americans of the U.S. commonwealth will continue to die unless the federal government ramps up its relief efforts.