President Donald Trump has reportedly been briefed on the London attack that left four dead on March 22, and is reported to have said that the attack was "big news."
The president reportedly apologized for being late to a meeting, saying, "we were just getting an update on London ... big news, just happened," according to the Independent. White House press secretary Sean Spicer said Trump had been briefed on the situation, and that he is continuing to "monitor and update."
Four people died in what authorities in London are calling a terror attack. The dead include a police officer and one man reportedly suspected to be the attacker. The attack, which occurred outside of the Houses of Parliament, also left 20 injured, with some victims left with "catastrophic" wounds, The Guardian reports.
The attacker reportedly drove a car into pedestrians on a nearby bridge before attempting to enter the parliament building with a knife. The suspect was reportedly shot by police outside the building.
"Since 2:40 p.m. this afternoon the Metropolitan Police Service has responded to an incident in the area of Parliament Square, and the Senior National Coordinator has declared this a terrorist incident," said Scotland Yard's Commander BJ Harrington of the incident.
"And although we remain open minded to the motive, a full counterterrorism investigation is already underway -- this is led by the Met's Counter Terrorism Command," Harrington added.
Police believe that there was only one attacker, but were reportedly searching the area, and asked anyone with photo or video of the incident to contact police.
"Public safety is our top priority and we are reviewing our policing stance across London and throughout the course of this afternoon there will be additional police and officers deployed across the capital," said Harrington.
A spokesman for the U.S. State Department, Mark Toner, said after the incident that the U.S. would try to help in any way that it could.
"We stand ready to assist in any way the U.K. authorities would find helpful," said Toner in a statement, adding that the U.S. Embassy in London was watching the situation closely and was prepared to help any U.S. citizens in the country.
"Our hearts go out to those affected," Toner said.
The New York Police Department also said it would be stepping up security at key locations, such as Grand Central Station and the British Consulate in New York City.
Spicer said Secretary of State Rex Tillerson and Secretary of Homeland Security John Kelly had issued statements on the incident and been in touch with British officials. Trump has also reportedly spoken with British Prime Minister Theresa May.
"I know the British government is investigating this now," said Spicer. "We're going to monitor the situation. We're staying in touch with British officials."