President Joe Biden responded to the New York City subway system shooting that left at least 29 injured on Tuesday as federal authorities in Washington assist New York officials in an intense manhunt for the suspect.

       Biden was briefed on the shooting earlier, White House press secretary Jen Psaki tweeted, before he departed for Iowa. Senior White House staff are also in contact with New York City Mayor Adams and Police Commissioner Keechant Sewell as the situation unfolds, she said.

       MORE: NYC subway shootings updates: Multiple shot, suspect at large

       En route to Des Moines, Psaki told reporters on Air Force One that she spoke with Biden aboard the plane about the ongoing situation and said the president reiterated a commitment to provide assistance to local leaders on the ground as the investigation continues.

       "Anything they need, anything they want. We are here to help them and provide that to them," Psaki said.

       Mandel Ngan/AFP via Getty Images

       President Joe Biden salutes as he makes his way to board Air Force One before departing from Andrews Air Force Base in Maryland, April 12, 2022.

       She said Biden and New York City Mayor Eric Adams have not yet had a phone call Tuesday.

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       The still at-large suspect -- who police said was wearing a green vest and a hooded gray sweatshirt -- is believed to have opened fire inside at least one subway station during morning rush hour traffic. There are at least three active crime scenes in Brooklyn. Authorities said at an earlier press conference that the lone gunman put on a gas mask, deployed a smoke canister, and when the subway car filled with smoke, opened fire inside the car and on the platform.

       Among those injured, according to the FDNY, 10 were shot. Five people are in critical but stable condition.

       The NYPD has informed the feds that police have a shared description of the suspect and that "investigators assess this was a coordinated attack, but the motive remains unclear."

       MORE: President Biden, NYC Mayor Eric Adams release plans to curb gun violence

       John Minchillo/AP

       Emergency personnel gather at the entrance to a subway stop in the Brooklyn borough of New York, April 12, 2022.

       Vice President Kamala Harris has received regular updates on the shooting, according to a White House official. Attorney General Merrick Garland and Department of Homeland Security Secretary Alejandro Mayorkas have also been briefed.

       Senate Majority Leader Chuck Schumer of New York tweeted that he is "closely monitoring" the unfolding situation in what he called "our beloved Brooklyn."

       "I'm grateful for the quick action of our first responders," he said. "To everyone in New York: Stay safe."

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       The shooting sparking panic across New York City comes as Adams has vowed to combat gun violence as mayor, on the rise since the pandemic.

       ABC News' Aaron Katersky, Josh Margolin, Alexander Mallin and Emily Shapiro contributed to this report.