VIENNA (Reuters) - Austrian police are investigating six Afghan refugees over sexual attacks on 18 women during New Year’s Eve celebrations in the western province of Tyrol, a police officer involved with the case said on Monday.

One man has confessed and apologized but the other five deny the accusations, Ernst Kranebitter of the Tyrol police force said, adding that police had made no arrests yet pending the end of their investigation.

The women reported that assailants had groped and tried to kiss them that evening as they stood in or near a crowded central square in the city of Innsbruck for a concert and fireworks display.

Some women said they had been clasped by a man from behind while others groped their breasts and genitals, said Kranebitter.

Some victims managed to take pictures of their assailants with their mobile phones, which helped police find the six men, who are aged between 18 and 22 and previously lived in the same migrant hostel, he said.

In neighboring Germany last year, hundreds of women were sexually assaulted and robbed at New Year’s celebrations in Cologne and suspects were mainly of North African and Arab appearance.

The Innsbruck assaults occurred despite an increased police presence following the previous year’s incidents in Cologne and also last month’s truck attack on a Christmas market in Berlin by a failed Tunisian asylum seeker.

Austria’s interior ministry says the country has seen around 130,000 people apply for asylum since 2015, when more than one million migrants and refugees arrived in Europe, many fleeing conflicts in the Middle East and Afghanistan.