Update: The student has surrendered and is being consoled by psychiatrists, Interfax reported.
Moscow police carried out negotiations with a teenager who came to school on Thursday morning with a knife and threatened to commit suicide, state media have reported.
Russia was rocked by a series of knife attacks at schools earlier this year. In October, a teenager killed 20 people in a shooting spree at a college in Crimea.
In the latest incident in Moscow’s southeastern Zhulebino district, a 16-year-old student first threatened teachers before saying he would kill himself, the state-run TASS news agency reported, citing an unnamed law enforcement source.
"According to preliminary reports, the motive for the act may be [the student's] poor grade; the upperclassmen is from a good family," the source was cited as saying.
The school's students and teachers were evacuated and no injuries were reported.
This story is developing.