The slogan “All Eyes on Rafah” has ricocheted across social media this week following an Israeli strike in the Gazan city that killed dozens of civilians and provoked international outrage.

For months, the phrase has been a touchstone in the social and cultural dialogue around Israel’s war against Hamas in the region. It has periodically trended on social media, particularly as Israeli military attacks in the city — located in the southern Gaza Strip, along the Egyptian border — have escalated.

On Wednesday, the saying was once again trending, this time through what appears to be an A.I.-generated image showing a field of refugee tents spelling out “All Eyes on Rafah.” One version of the graphic has been shared more than 38 million times on Instagram.

The phrase may have originated in comments made in February by Rik Peeperkorn, who heads the World Health Organization’s office for Gaza and the Israeli-occupied West Bank. Mr. Peeperkorn was speaking at a news conference as the Israeli military intensified its campaign in the southern Gaza strip.

“All eyes are on Rafah,” Mr. Peeperkorn said at the time.

The comment was almost immediately repurposed by pro-Palestinian and humanitarian groups to draw attention to Gaza and Rafah, which was one of the last remaining destinations for displaced Palestinians from other parts of the territory. Among them were Save the Children International, Oxfam and, later, pro-Palestinian lobbying groups like Jewish Voice for Peace.

The saying was also heard at pro-Palestinian protests that swept across Western universities earlier this month.

The deadly strike in Rafah on Sunday was quickly denounced by world leaders. Prime Minister Benjamin Netanyahu of Israel said the attack had killed two Hamas officials, and he called the civilian deaths a “tragic accident.”