The prosecutor in Beijing's Xicheng District has decided to arrest a 49-year-old male who injured 20 primary school students in a hammer attack on January 8.

The arrest was approved on Monday and prosecutors said the suspect would be charged with intentional homicide.

The 49-year-old with surname Jia was a maintainer at the Beijing No. 1 Affiliated Elementary School of Xuanwu Normal School and carried out the attack after his work contract was not renewed.

Nineteen of the injured students have been discharged from the hospital as of late Sunday, Xicheng government said, adding they have been provided with proper physical and mental aftercare.

The only one who's still receiving treatment in the hospital is gradually recovering, according to a government statement on its social media platform Weibo.