Updated

Scientists say they have more evidence that an increase in earthquakes on the Colorado-New Mexico border has been caused by wells that inject wastewater from oil and gas production back underground.

A paper published last week by researchers at the University of Colorado concludes the wastewater increased underground pressure enough to make rock formations slip along fault lines.

It's the latest report to link wastewater injection wells to earthquakes. Quakes in Kansas, Oklahoma and Texas also have been linked to the practice.

Most oil and gas wells produce at least some wastewater that's too salty to use, so regulators allow energy companies to pump it back underground to get rid of it.

The Journal of Geophysical Research: Solid Earth published the University of Colorado study.