A Rivers, Man., teen charged in an alleged plan to attack his school in March now faces additional charges, including conspiracy to commit murder.

He’s also charged with counselling the offence of murder and two counts of uttering threats, RCMP said in a news release Thursday morning.

He was rearrested Wednesday at the Manitoba Youth Centre.

The 14-year-old was originally arrested on March 16 by Manitoba RCMP and charged with uttering threats.

Police allege he and another teen in Bridgewater, N.S., planned to simultaneously attack their schools — Rivers Collegiate in Manitoba and Park View Education Centre in Nova Scotia.

Rivers Collegiate is a Grade 7-12 school with fewer than 150 students in the community of fewer than 1,000 people, which is about 225 kilometres west of Winnipeg.

Interpol and the FBI tipped off Bridgewater police about online communications planning school attacks.

Police allege conversations between the two teens started in mid-February, with the teen from Rivers “actively discussing and planning to harm other students at Rivers Collegiate.”

The teen was arrested on a bus on the way to school.

At the time, RCMP spokesperson Cpl. Melanie Roussell said it was “the safest way for us to take him into custody, prior to him attending school,” but “the threat was not imminent.”

Police searched two properties associated with the accused, seizing more electronic devices and two firearms owned by a relative.

The Rivers youth has been in custody since his initial arrest. He’s expected to appear in court next on June 4.