RIPON, California – Four children have been diagnosed with cancer at Weston Elementary School in San Joaquin County, California.

Some parents believe it’s because of radiation caused by a cell phone tower.

Monica Ferrulli talked to KOVR.

“We had a doctor tell us that it’s 100 percent environmental, the kind of tumor that he has,” Monica said.

Monica’s son Mason was the second child to be diagnosed with cancer in just 3 years. He received treatment, then relapsed and is currently undergoing brain cancer treatments.

Joe Prime’s son Kyle was the first, diagnosed with kidney cancer in 2016. And two more kids were diagnosed this year.

“It just seems like coincidence is no longer a reason for all this illness,” Prime said.

They believe it’s this cell phone tower that’s harming their kids.

The district has had several tests done saying the tower is safe and meets federal regulations.