MIDDLETOWN — The Middletown superintendent of schools has resigned, citing recent threats to him and his family, which caused him to "reevaluate personal priorities."

"At this time, my priority is my family," Michael Conner wrote in the letter addressed Thursday to Board of Education Chairwoman Deborah Cain.

Conner's letter said he planned to have his resignation take effect in 90 days.

However, Cain accepted his resignation, effective immediately, according to Middletown Public Schools Communications Director Jessie Lavorgna.

"The Board wishes Dr. Conner well in his future endeavors," Lavorgna wrote in an email.

Conner received he called a "hate packet," containing death threats and racially charged language mailed to his home.

The schools chief reported the incident to police, who are investigating the matter.

Conner has been on leave from his job since mid-October, after the district launched an independent investigation into alleged misconduct by top school district administrators.

"I am not resigning because of the baseless claims, political posturing, and a one-sided investigation process that is more interested in reaching a result in lieu of finding the truth," Conner wrote in the resignation letter.

Conner's wife Viviana Conner described the material as racist, hateful and threatening. She believes media coverage of the school board probe has "emboldened" and "enabled" the individual whose name was on the letter.

Since no charges have been filed, Hearst Connecticut Media Group is withholding the identity of the person.

"I will be making an extensive outreach and communication to this community in the coming weeks," Michael Conner said in his resignation letter.