A young couple that worked at the Israeli embassy was shot dead outside a Jewish museum in Washington on Wednesday evening by a gunman.

The gunman who was allegedly chanting “free Palestine’’ while being arrested, local and federal law enforcement authorities said.

U.S. President Donald Trump and Secretary of State Marco Rubio described the killings as anti-Semitic hate crimes.

“These horrible D.C. killings, based obviously on antisemitism, must end, NOW!,’’ Trump wrote on his Truth Social platform.

In Israel, Prime Minister Benjamin Netanyahu’s office said the leader was “shocked’’ by the horrific, anti-Semitic shooting and announced that security was being increased at its diplomatic missions around the world.

“We are witnessing the terrible price of anti-Semitism and wild incitement against Israel.

`The blood libels against Israel are costing us blood and must be fought relentlessly,’’ that statement said.

Washington police chief Pamela Smith named the suspect as 30-year-old Elias Rodriguez of Chicago.

She said that he had been seen pacing back and forth outside the Capital Jewish Museum, in central Washington, before opening fire and killing a man and a woman.

U.S. Homeland Security Secretary Kristi Noem and Israeli leaders said the victims worked at the Israeli embassy.

According to Israeli ambassador to the U.S., Yechiel Leiter, they were a young couple who were about to get engaged.

The man had apparently bought a ring and planned to propose to his girlfriend in Jerusalem the following week.

The American Jewish Committee (AJC), an advocacy group, was hosting its annual Young Diplomats reception at the museum on Wednesday night.

“We are devastated that an unspeakable act of violence took place outside the venue.

“At this moment, as we await more information from the police about exactly what transpired, our attention and our hearts are solely with those who were harmed and their families,’’ the group said in a statement.

Whether the suspected shooter knew the two or what connection he might have to them is unclear.

According to Washington police, the perpetrator approached a group of four people and then opened fire.

After the shooting, he entered the museum, where he was arrested by private security guards and chanted “free, free Palestine.’’

The FBI said it is investigating the case as a possible hate crime.

Senate Minority Leader Chuck Schumer, the highest-ranking Jewish elected official in the U.S., said.

“This sickening shooting seems to be another horrific instance of antisemitism which as we know is all too rampant in our society.

“I’m praying for those who were killed, all those affected, and their families.’’

The shooting occurred after Israel’s military recently launched a major offensive in the sealed-off Gaza Strip, where around two million Palestinians live.

Israel’s actions in the region are facing increasing international criticism, including from close allies.

The conflict in Gaza began on Oct. 7, 2023, when Palestinian militant organisation Hamas and other terrorists invaded Israel, killing 1,200 and taking some 250 hostage.

Israel responded with a massive attack, which has since killed more than 53,000 in Gaza, according to the Hamas-controlled health authority.

The figures do not distinguish between civilian and militant casualties.