Police in Switzerland have arrested a 75-year-old woman on suspicion of killing a seven-year-old boy who was fatally stabbed on his way home from school.

The child was attacked while walking alone in the north-western city of Basel at about 12.30pm local time (1130 GMT), police said.

The boy’s teacher found him lying on the ground in a serious condition and called for an ambulance. Despite efforts to resuscitate him, he was declared dead at the hospital, police said.

Shortly after the stabbing, a 75-year-old woman turned herself in to authorities. She admitted attacking the child and was arrested.

Police said investigations were continuing and appealed for witnesses.