GENEVA — The United Nations experts investigating human rights conditions in North Korea said Tuesday that the “shocking” evidence they had collected from defectors and others suggested “large-scale” patterns of abuse that demanded an international response.

The Human Rights Council pushed for the investigation in an attempt to bring new attention to allegations of horrifying abuses at the North’s infamous gulags that have been trickling out for years as more people have escaped the brutal police state. Until now, world powers including the United States had focused instead on attempts to dismantle the North’s nuclear weapons program.

The chairman of the three-member Commission of Inquiry, Michael Donald Kirby, told reporters that the testimony he had heard in recent months evoked reactions similar to the discovery of concentration camps in Europe after World War II.

He cited the statements of a former prisoner who said she had seen another woman forced to drown her baby in a bucket, and the account of a man who said he had collected and burned the bodies of prisoners who had died of starvation. Experts say the number of prisoners in gulags has dropped in recent years — to an estimated 120,000 or fewer from a possible high of 200,000 — but that might be partly because so many had died from forced labor and a lack of food.