AKIPRESS.COM - Twenty primary school students in Beijing have been injured in an attack at their school by a hammer-wielding man, say officials in China, BBC reports.

The attack took place at around 11:00 local time (03:00 GMT) said Beijing's Xicheng district in a statement on social media site Weibo.

Three children were reported to be seriously injured but stable.

The alleged attacker has been arrested. It is not clear what motive the suspect might have had.

Some reports say he was a former maintenance worker at the school.

The attack took place at the Beijing No.1 Affiliated Elementary School of Xuanwu Normal School, according to state-media outlet the Global Times.

The Xicheng district said it would work together with other government authorities to carry out a full investigation.

The attack comes after a Chinese man was executed on Friday for injuring 12 children in a knife attack at a nursery in China.

Violent crime is rare in China but there have been several attacks on school children in recent years.