Nearly 1 in 6 children in Gaza are acutely malnourished after two years of war that has caused severe food shortages in the Palestinian territory, according to a study published Thursday.

The study, published in medical journal The Lancet, comes after the United Nations in August declared a famine in parts of the Gaza Strip — a finding rejected by Israel, which has imposed a blockade on the territory as it wages war on Palestinian Islamist group Hamas.

"After nearly 2 years of war and severe restrictions in humanitarian aid, tens of thousands of preschool-aged children in the Gaza Strip are suffering from preventable acute malnutrition and facing an increased risk of mortality," said the study, financed by the U.N. Palestinian relief agency, UNRWA.