In yet another alarm about how unaccompanied migrant minors staying in overcrowded detention centers on Greek islands are being treated, the United Nations Children’s Fund (UNICEF) said other European Union countries who closed their borders to refugees and migrants should do more to help.

There are more than 1,100 of the minors in the camps, said UNICEF. “We continue to appeal to Greek authorities to transfer children to adequate accommodation on the mainland, but Greece cannot support refugee and migrant children alone,” UNICEF’s regional director for Europe and Central Asia Afshan Khan said from the agency’s headquarters in Geneva, reported Kathimerini.

“It is vital that European governments increase pledges to relocate unaccompanied and separated refugee and migrant children, and fast-track family reunifications for those who already have relatives in Europe,” she added.

That came after a 15-year-old Afghan boy was stabbed to death the previous week at the notorious Moria camp on the island of Lesbos that the BBC called “the worst in the world” and with the new New Democracy government yet not acting to make improvements.

“This latest tragedy is a stark reminder that the situation in reception centers in Greece is at a breaking-point,” Khan said, joining a chorus of other groups who have been ignored by successive administrations and with the EU doing little to help.

Built to house 3,000 people, the Moria facility is hosting more than 8,700, including some 3,000 children, according to UNICEF. There are 520 unaccompanied children at a special section of the camp which was made to hold 160. Overall, Greece is hosting more than 32,000 child migrants of whom 4,100 are unaccompanied.

There are more than 22,700 refugees and migrants in the island camps and another 50,000 in facilities on the mainland with the crisis more than four years old and showing no signs of abating, with Turkey continuing to let human traffickers send more to Greek islands.

An EU swap deal with Turkey, where the refugees and migrants first went, fleeing their homelands in the Middle East in hopes of reaching more prosperous countries before the doors were closed, has seen only a relative handful who weren’t eligible for asylum being returned so far, although New Democracy said the pace would pick up at some point.