Hong Kong police said yesterday they had arrested eight people in connection with a knife attack on a seven-year-old boy which shocked the territory.

One of the people arrested was the victim’s step-mother, Senior Superintendent K.K. Chan told a news conference. Six of them were arrested in Hong Kong and the other two in mainland China.

Shum Ho-yin was walking with his grandmother near their home on Aug. 25 when they were jumped by two masked men with knives who pushed him to the ground and started slashing him. He suffered six wounds to his arm and leg.

“We believe that motive of the attack is not related to triad (organised crime), debt collecting, loan shark activities or mental problems. We believe that the case is derived from a family problem and dispute”, Chan said. He declined to elaborate.

Chief Executive Donald Tsang had described the attack as “angering God and men’” and vowed to bring those responsible to justice.