As Jewish people prepare to celebrate the first night of Passover, some plan to leave a seat open at their Seders – the meal commemorating the biblical story of Israelites' freedom from slavery – for a Wall Street Journal reporter recently jailed in Russia.

Agents from Russia's Federal Security Service arrested Evan Gershkovich a week ago in the Ural mountain city of Yekaterinburg and have accused him of espionage. The Wall Street Journal denies that allegation, and on Wednesday, Secretary of State Antony Blinken said he had "no doubt" that Gershkovich was wrongfully detained. This is the first time Moscow has detained a journalist from the US on espionage accusations since the Cold War.

"It feels like an attack on all of us," said Shayndi Raice, the Wall Street Journal's deputy bureau chief for the Middle East and North Africa.

"We're all kind of in this state of 'how can we help him, what can we do,'" Raice said. "It's really horrific and it's just terrifying."

Raice is one of several Jewish journalists at the Wall Street Journal who have launched a social media campaign advertising that they will keep a seat open at their Seder tables for Gershkovich. They plan to post photos of the empty seats on social media.

The tradition of leaving a place open at the Seder table isn't new. Raice says that going back decades, many Jews left seats open on behalf of Jewish dissidents imprisoned in the Soviet Union.

Now, she's bringing the idea back, to raise awareness about her colleague who has been held by Russian authorities since March 29.

"We want as many people as possible to know who Evan is and what his situation is," Raice said. "He should be somebody that they care about and they think about."

Rabbi Shmuly Yanklowitz, president of the Scottsdale, Arizona-based Jewish nonprofit Valley Beit Midrash, has joined the effort to encourage other Jews to leave an empty seat at their Seder tables for Gershkovich. He shared the campaign poster on Twitter and has talked about it in his Modern Orthodox Jewish circles. Yaklowitz's own Seder table will include a photograph of the jailed journalist, as well as a seat for him. He also plans to put a lock and key on his Seder plate – a dish full of symbolic parts of the meal that help tell the story of Passover.

Yanklowitz says the lock and key represent confinement – Gershkovich's confinement, but also as a theme throughout Jewish history.

"We have seen tyrants," Yanklowitz said. "We have seen tyrants since Pharaoh all the way up to our time with Putin. And these are tyrants that will only stop with pressure and with strong global advocacy."

The Wall Street Journal says Gershkovich's parents are Jews who fled the Soviet Union before he was born. His lawyers were able to meet with him on Tuesday, nearly a week after his arrest. Dow Jones, which owns the Wall Street Journal, said in a statement that the lawyers tell them Gershkovich's "health is good."

Miranda Kennedy edited this story for digital.