NEW YORK — Ikea is recalling 29 million chests and dressers after six children were killed when the units toppled over and fell on them.

The chests and dressers are unstable if they are not secured to a wall, the U.S. Consumer Product Safety Commission said Tuesday.

All of the children killed were 3 years old or younger, the CPSC said. One child was killed about 27 years ago. The other deaths were more recent, between 2002 and 2016. The CPSC said it also received 36 reports of children who were injured.

The recall, which only applies to customers in the U.S. and Canada, is for several types of Ikea chests and dressers. Ikea said the units under the recall are children’s chests and drawers taller than 23.5 inches and adult chests and dressers taller than 29.5 inches.

The recalled units were sold at Ikea stores for years.

The Swedish retailer said that anyone who owns one of those chests and dressers, and have not attached them to a wall, should remove it out of reach from children. Ikea is offering free kits to attach the chests and dressers to a wall.

Customers that don’t want to keep the recalled furniture can ask for a refund. Ikea said it will give a full refund to owners of recalled chests and dressers made between 2002 and 2016. For recalled units made before 2002, customers can receive a store credit for half the original price.

Ikea USA President Lars Petersson said the chests and dressers were sold with instructions saying that they had to be mounted to walls. Last year, the company offered free wall-mounting kits to owners of its Malm chests and dressers after reports of children’s deaths.