Brussels - The 20-year-old man suspected of killing two toddlers and a teacher in a knife attack at a Belgian nursery in January has confessed to the murder of a pensioner.

Kim De Gelder admitted his involvement in the death of 73-year-old Elza Van Raemdonck de Vrasene during a court hearing, the Belga news agency reported Tuesday.

Belgian investigators had linked the young man to the death of the pensioner - found stabbed to death in her home in the East Flemish town of Beveren on the evening of January 16 - not long after his arrest over the January 23 kindergarten massacre.

De Gelder, who is being held in custody, is accused of talking his way into a day-care centre in town of Dendermonde and attacking the children and teachers there with a knife. Two toddlers and one carer died in the attack, and 10 children and two adults were injured. (dpa)