Four people remain unaccounted for and are believed to be trapped beneath the rubble after an Iranian ballistic missile slammed into a residential building in Haifa, according to Israel Police Commissioner Danny Levy at the scene.

“We are concentrating all efforts on locating the four family members who are supposed to be here, using every tool at our disposal,” Levy said, as rescue teams continue a high-risk search operation.

Authorities are also dealing with a dangerous complication, the missile’s warhead may not have detonated on impact. “We have evacuated multiple surrounding buildings out of concern that the warhead could still explode,” Levy warned.

Bomb disposal units are now working against the clock at the site, as emergency crews race to reach those still believed to be trapped beneath the debris.