LAS VEGAS (AP) A review of private inspector reports at the site of the $8.6 billion CityCenter construction project on the Las Vegas Strip shows construction moved forward in hundreds of instances without engineering approval.

The review by the Las Vegas Sun shows that in those instances, contractors worked from last-minute drawings that had not been approved by Clark County, but affected buildings’ structural integrity.

County spokesman Dan Kulin said county inspectors normally review the so-called “noncompliance reports” to see that the project is built to code in spite of the unauthorized fixes.

The county officially requires engineering changes to be approved before they are implemented.