On the night of August 2, 1999, a massive landslide occurred in Cherry Hills subdivision in Antipolo, Rizal, Philippines that resulted to about 60 deaths and 378 houses buried.

[1][2] The landslide was primarily caused by the heavy rains associated with Typhoon Ising (Olga) and neglect by the developers and government officials in assessing the site's vulnerability to geohazards.

On August 3, 1999, the landslide occurred as other residents were preparing to evacuate due to heavy rain, trapping them inside their homes as uphill houses and 45,000 cubic meters of mud, rocks, and concrete buried low-lying areas.

However, Philjas officials later acknowledged that quarrying by the company on a mountain that left a 20-foot high hanging wall made the site unstable and that they had failed to present a geohazard assessment before commencing construction.

[8] A study by geologists at the University of the Philippines also attributed the cause to the geological setting of the area, noting that its soil was oversaturated with water as it consisted of alternating porous and impervious rocks as well as a significant amount of clays "of probably the swelling type."

They also cited the natural slope of the ground, sparse vegetation, and pre-existing fractures in the bedrock, and concluded that a geological survey could have avoided the event, which geologists said was probably not conducted to save on construction costs.

[9] An investigation by the Philippine Senate concluded that the disaster was not caused by force majeure, but occurred as a result of the negligence of Philjas and government agencies, which failed to enforce rules on the construction of low–cost housing.