LAND O’ LAKES, Fla. (AP) _ A Florida science teacher has been suspended for running a signal jammer to prevent his students from using their cellphones in class.

School board members in Pasco County approved Dean Liptak’s five-day, unpaid suspension on Tuesday. Liptak didn’t contest the decision.

Officials say Liptak activated the jammer in his Fivay High School classroom from March 31 through April 2. He later told a school district investigator that he never intended to cause problems. He said he thought the jammers were allowed as long as they were not intended for malicious purposes.

Superintendent Kurt Browning wrote in a reprimand letter that Liptak had potentially violated federal law and that the signal jamming could have potentially interfered with others trying to call 911 during an emergency.