BEIJING, Jan. 8 (CGTN) -- At least 20 children were injured, three in critical condition, after a man attacked students in an elementary school in central Beijing's Xicheng District on Tuesday, according to local authorities.

The incident took place around 11:17 a.m. local time. All injured have been hospitalized and the assailant has been overpowered.

An investigation into the motive behind the attack is underway.