A migrant worker who seriously injured his wife and 1-year-old son in separate incidents has once again put the spotlight on the lack of psychological support for the nation's floating population.

The 31-year-old man, surnamed Chen, stabbed his wife in her abdomen with a knife during an argument over their children's upbringing. Then, when he came to visit her at Shanghai's Renji Hospital with their 1-year-old son, he severely injured the toddler by throwing him on the floor headfirst.

"The man became out of control when talking on his phone, and he threw the boy to the ground - hard," said a witness surnamed Wu.