A geological fault in Tijuana appears to have caused the collapse of four houses on Saturday, and damage to several others.
Residents of the Reforma neighborhood of the border city first noticed cracks in the walls of their homes two weeks ago. On Friday, when the cracks started to grow larger, they notified municipal authorities, who ordered the evacuation of 11 homes after an inspection revealed there was a high risk they would collapse.
By Saturday, a total of 22 homes had been identified as being at risk and their occupants evacuated. Later in the day, four of the dwellings collapsed.
The municipality issued a statement saying a natural geological fault was responsible.
The area has been cordoned off by local officials to avoid casualties and prevent looting and electrical and water services have been suspended.