Farmington police say they arrested a man who invoked the Newtown elementary school massacre in text messages he sent threatening to shoot an former girlfriend. Farmington police say Darnell Davis, 31, of Avon threatened in messages sent on Dec. 17 to shoot his former girlfriend and her young son and carry out crimes similar to the massacres in Newtown and at Columbine High School in Colorado. Davis was arrested Thursday on charges including second-degree breach of peace, threatening, and harassment. He is being held on $750,000 bond. A phone number was not listed for Davis’s address. Authorities say that no guns were found at Davis’s residence and that police do not believe he owns guns. He was arrested on behalf of Hartford police who were investigating a complaint from Davis’ former girlfriend.