IDF computer operations room
IDF computer operations roomIsrael news photo: Flash 90

Authorities were astounded to discover Sunday that the name of a top-secret IDF unit, as well as the commander who heads the unit, had been leaked online for over a year and a half.

IDF Radio reported Sunday that the name - which has not been released for publication - was revealed in the text of a thank-you letter to the unit by the Civil Administration. The letter was apparently posted online and remained up and available for public viewing for over 18 months, according to the report. 

A request from the poster eventually brought the letter down, and it was deleted from the system. The officer responsible for investigation has been reprimanded and an investigation has been launched, according to an IDF spokesman. 

The unit itself is also being questioned - not on sending the thank-you letter, which is a matter of professional courtesy, but why the decision was made to include the full name of the unit as well as members of the staff. 

Mishaps with classified information have become more common as technology progresses. Earlier this month, several IAF pilots were reprimanded after they stored sensitive maps and flight plans on their smartphones. Two were jailed and another 12 were fined over the incident.