A former FBI agent who pleaded guilty to child pornography charges earlier this year will also plead guilty to leaking classified information about an Al Qaeda bomb plot to The Associated Press -- in a case of spilled secrets that the Justice Department called one of the most serious in U.S. history.

Donald John Sachtleben of Carmel, Ind., a former FBI technician and government contractor, has signed plea agreements in both cases, the U.S. attorney’s office said Monday.

“I am deeply sorry for my actions,” Sachtleben said in a written statement. “While I never intended harm to the United States or to any individuals, I do not make excuses for myself. I understand and accept that today’s filings start the process of paying the full consequences of my misconduct, and I know that the justice system I once served so proudly will have its say."

Charges in the child pornography case against Sachtleben were filed in May 2012 after law enforcement officials said they found child porn they were able to trace to his home computer. That complaint alleges that an examination of Sachtleben’s laptop revealed the presence of about 30 images of child porn that he is accused of trading with other people using the email address pedodave69@yahoo.com.

Nine days before those charges were filed, prosecutors say Sachtleben gave up national defense information to a news reporter related to a disrupted terrorist plot.

The documents in the AP leaker case were filed Monday in the U.S. District Court for the Southern District of Indiana.

Charging documents allege Sachtleben knew that information would compromise national security. They also claim the information related to a foiled plot by Yemen-based terrorist organization Al Qaeda in the Arabian Peninsula to bomb a U.S.-bound airliner.

“We were given the task of uncovering who had threatened a sensitive intelligence operation and endangered lives by illegally disclosing classified information relating to a disrupted Al Qaeda suicide bomb plot,” U.S. Attorney Ron Machen said. “That plot could not have been more serious. … This prosecution demonstrates our deep resolve to hold accountable anyone who would violate their solemn duty to protect our nation’s secrets and to prevent future, potentially devastating leaks by those who would wantonly ignore their obligations to safeguard classified information.”

The investigation into who leaked top secret information to the AP began a national debate over the rights of the press.

AP President Gary Pruitt said at the time that “there can be no possible justification for such an overbroad collection of the telephone communications of The Associated Press and its reporters.”

Sachtleben had been employed in the Department of Forensic Sciences at Oklahoma State University. He spent over 25 years as a special agent bomb technician in the FBI before retiring in 2008. He specialized in counter terrorism and bombing investigations.