Spanish officials say at least 180 people have been evacuated in the northern coastal city of Ondarroa after days of heavy rain caused a rock cliff to partially collapse, threatening a row of newly built apartment buildings.

Mayor Zubeltz Bedialauneta says experts had warned that a rocky cliff behind the new apartments had shown slippage after nearly a week of heavy downpours and it finally began to give way on Friday afternoon. He says the local government decided to evacuate residents Saturday after boulders struck the rear of the buildings.

He says there's still a danger that the rest of the cliff could collapse onto the apartments.

City spokeswoman Leire Beitia says the latest tests showed "the state of the cliff face has worsened alarmingly."