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.
At least three others were trapped, and contact had been made with two of them, police 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.
