Frits Leo Versteegh, the 75-year-old man jailed Dec. 4 after he emailed a threat to blow up San Diego Gas & Electric (SDG&E) work trucks in a land-use dispute, pleaded not guilty Dec. 12 to making a false bomb report, according to the San Diego Reader.

Versteegh was taken into custody late on Dec. 4, after he reportedly sent an email to a local news station’s website, in which he threatened to bomb SDG&E trucks.

NBC 7 said on its website that it received the email, which said SDG&E had recently installed a metal post on Spearhead Trail and damaged a dirt wall that kept the road from being washed away. An SDG&E official said the installation project began in October, reported UT San Diego.

The news station said Versteegh claimed he didn’t get the response he wanted when he called the utility company so he was going to take “the matter into my own hand now.” His email said he was burying a home-made mine to target company trucks, and that he would put up a warning sign.

Bomb and arson investigators were unable to find any explosive device after two hours of searching, according to Sheriff’s sergeant Alan Noble, as reported by the San Diego Reader.

Judge Martin Staven ordered Versteegh to surrender any firearms he might possess, at the request of prosecutor Cal Logan.

Versteegh is next due in San Diego’s North County Superior Courthouse on Jan. 5, 2015.

A photo of Versteegh can be viewed on The Valley RoadRunner website.