Details were still emerging of the incident at the construction site in northeastern Tel Aviv where an underground car park collapsed.
Police reported 18 wounded, including one seriously, one moderately and 16 lightly.
Israeli television images showed medics walking across rubble, twisted iron bars and dirt as they carried a wounded person away on a stretcher.
Other medics with stretchers as well as ambulances waited nearby on standby. Search-and-rescue dogs were also at the scene.
At least seven had been trapped, and contact had been made with two of them, police said. Those two were later rescued, they said.
The army said it sent search and rescue forces to “extract civilians”.
United Hatzalah medical service also said “firefighters and rescue teams are working to extricate” those believed missing.
“It appeared to me that the roof of a parking garage had collapsed in the building site,” United Hatzalah quoted one of its medics as saying.
“While members of our ambu-cycle unit who arrived first on scene were treating the injured, reports came in of other people who were unaccounted for and likely still trapped inside.”
Images of the scene showed an underground car park that had caved in and dozens of rescue workers and security forces at the site in Tel Aviv’s Ramat Hahayal neighbourhood.
Ramat Hahayal is home to a number of high-tech offices in Israel’s booming technology industry, based around the city of more than 400,000 people.
Israel has seen an unusually high number of construction accidents in comparison to the developed world.
Israeli newspaper Haaretz reported in May that 480 people were killed in construction accidents between 2000 and 2015.
The survey placed Israel third from the bottom in a list that included the United States and 20 European nations, ahead of Cyprus and Portugal, Haaretz said, citing a report from the economy ministry and National Insurance Institute.
The economy ministry said in response that it would focus on enforcing construction industry regulations.
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