Two teenagers charged with plotting to attack their New York middle school with guns and explosives have pleaded guilty to conspiracy, prosecutors said Wednesday.

The boys appeared in Orleans County Family Court Tuesday, where they admitted their part in what investigators said in November was a credible threat against Albion Middle School.

A third boy is due in court later this month.

The three, all younger than 16, were charged as juveniles with conspiracy to commit murders after police said they set a date to attack the rural western New York school using explosives and firearms. Authorities said no explosives were recovered during searches of the boys’ homes, but police found legally possessed firearms.

The threat started on an online gaming app, authorities said.

Both of the boys who appeared Tuesday pleaded guilty to conspiracy. One also pleaded guilty to aggravated harassment. They could be detained or receive conditional discharges when they appear for a disposition hearing Feb. 25, the county district attorney’s office said.

The boys have been barred from school grounds and the use of electronic devices since their arrests.

(AP)