Israeli Embassy staffers killed: The final hours of Yaron Lischinsky and Sarah Milgrim

WASHINGTON - Yoni Kalim attended the American Jewish Committee event Wednesday night at the Capital Jewish Museum, where he spent time with Israeli Embassy staff members 30-year-old Yaron Lischinsky and 26-year-old Sarah Milgrim before they were tragically gunned down.

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What we know about Yaron Lischinsky and Sarah Milgrim?

Yoni Kalim was at the American Jewish Committee event on Wednesday night at the Capital Jewish Museum and spent time with Yaron Lischinsky and Sarah Milgrim before they were tragically gunned down.

Victims' final hours

What we know:

The event aimed to bridge gaps among Muslim, Christian, and Jewish organizations working together to provide humanitarian aid to Gaza. Kalim met Lischinsky, 30, a research assistant, and Milgrim, 26, who coordinated visits and missions to Israel. The gathering included staffers from more than 30 embassies, State Department officials, and young professionals.

Kalim said he and others heard 10 to 15 gunshots shortly after 9 p.m. Moments later, the suspect entered, but no one initially realized he was the gunman. "I wasn't fully aware that he was the suspect. I am very used to seeing pro-Palestinian protesters at Jewish events and Jewish spaces. It's quite common. So for us to make the jump that he happened to be related to those gunshots didn't happen until much later when many of us at the event started to put pieces together," he said.

"I'm still in a state of shock right now. The community is reeling from these losses," Kalim told FOX 5. "What started off as a beautiful evening with a lot of education, and hope, and love turned into a horrific nightmare."

Witness spoke with suspect after deadly Jewish museum shooting

Katie Kalisher said she heard gunshots and spoke with the man who allegedly shot and killed two Israeli Embassy staff members outside of the Capital Jewish Museum in Washington, D.C. on Wednesday.

READ MORE: 2 Israeli Embassy staff members killed in shooting outside DC’s Capital Jewish Museum identified

Engagement plans tragically cut short

He said he had interacted with Lischinsky and Milgrim at the event and was devastated to learn they had been killed. "It's absolutely horrific. I mean, I interacted with them at the dinner. "I interacted with them throughout the event, and to find out that they were just gunned down -- shot 10, 15 times -- is horrific." While he didn't know the couple very closely, he noted that he and his family had mutual friends with them, as is common in the Jewish community.

FOX 5 has learned that the couple was preparing to get engaged, with Lischinsky having purchased a ring earlier this week and planning to propose in Jerusalem next week. "It's a senseless act of horror that I'm hoping will never happen again," Kalim said.

READ MORE: Witness unknowingly spoke with suspected gunman after deadly shooting outside Capital Jewish Museum

Witness spoke with suspect after deadly Jewish museum shooting

Katie Kalisher said she heard gunshots and spoke with the man who allegedly shot and killed two Israeli Embassy staff members outside of the Capital Jewish Museum in Washington, D.C. on Wednesday.

"That could have been me."

Calling the incident an act of domestic terrorism, Kalim said the couple was simply in the wrong place at the wrong time. "I don't know how he happened to stumble upon the two Israeli Embassy staffers, but I was looking to call my Uber around the same time, but my wife decided she wanted to stay a little longer. So that could have been me."

Kalim also raised concerns about security lapses during the event. "After we heard the gunshots, the protocol should have been to lock down the place," Kalim said. "However, we did have people come in that were already with the event, they had their name tags. The person in custody now, he did have a suit on. So he did look like he could have been one of us."

"I do think protocols were breached," Kalim said. "He was let in, and thank God he didn't have a weapon on him because we were with him for, I don't know, 10, 15 minutes."

Israeli Embassy staffers killed: The final hours of Yaron Lischinsky and Sarah Milgrim