A woman holds a baby as migrants wait to get on the bus at a camp on the border with Slovenia in Spielfeld, Austria, Thursday.

Unidentified gunmen have staged a series of new sabotage attacks on boats carrying migrants cross the Aegean Sea, Human Rights Watch said on Thursday.

Quoting witnesses, the New York-based rights group said there had been eight incidents in which gunmen “intercepted and disabled the boats carrying asylum seekers and migrants from Turkey toward the Greek islands.”

The most recent incidents were on October 7 and 9.

According to a 17-year-old Afghan called Ali, a speedboat with five men armed with handguns had rammed their rubber dinghy on October 9.

“At first when they approached, we thought they had come to help us,” he told HRW.

“But by the way they acted, we realized they hadn’t come to help. They were so aggressive. They didn’t come on board our boat, but they took our boat’s engine and then sped away,” he said.

He said the men attacked three other boats in quick succession before speeding off toward the Greek coast

“They spoke a language we didn’t know, but it definitely was not Turkish, as we Afghans can understand a bit of Turkish,” he said.

Similar allegations were made by both migrants and rights groups during the summer.

The latest attacks took place near the island of Lesbos, HRW said.

Police said Thursday that Crimes targeting refugee centers in Germany have risen sharply, cautioning that the crisis was fueling the risk of attacks on politicians by far-right extremists.

The warning by Germany’s Federal Criminal Police Office (BKA) comes after a mayoral candidate in the eastern city of Cologne was stabbed in the neck in an attack apparently motivated by her work with refugees.

The United Nations rights chief on Thursday accused Czech authorities of systematically detaining migrants and refugees in “degrading” conditions, as part of a policy to dissuade them from entering the country.

Several European countries have in recent months introduced measures to curb the flow of tens of thousands of refugees and migrants on the move across the continent.

But UN High Commissioner for Human Rights Zeid Ra’ad Al Hussein said only the Czech Republic was routinely detaining them for 40 days, and in some cases reportedly up to 90 days, “in conditions which have been described as degrading.”

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