The US government and Ivanka Trump on Monday expressed sympathy with worshippers attacked while leaving a London mosque -- while the president himself remained silent.
State Department spokeswoman Heather Nauert issued an official condemnation of the deadly assault but Donald Trump -- often quick to comment on Twitter after extremist violence -- kept his counsel.
"The United States strongly condemns last night's attack that appears to have targeted Muslim worshippers in London," Nauert said.
"We extend our sympathies to the families and community of the victims and our hopes for the quick recovery of those wounded."
Trump's daughter and adviser Ivanka also reacted to the attack.
"Sending love and prayers to the victims in #FinsburyPark London. We must stand united against hatred and extremism in all it's ugly forms," she tweeted.
President Trump has taken to Twitter during previous terror attacks to make the case for tighter restrictions on travel from predominantly Muslim countries.
He has also yet to offer public comment on the deaths of seven US sailors, killed during a collision between their navy destroyer and a Philippine-flagged cargo ship.
In London, a van ploughed into a crowd near a mosque early on Monday, leaving one person dead and injuring 10 others in the second terror attack this month in the city.
Prime Minister Theresa May condemned the "sickening" incident, reaffirming Britain's determination to fight "terrorism, extremism and hatred."