The sliced portion of thumb was restored in an emergency operation yesterday at Bangkok Hospital Phuket, Phuketwan has learned. One of her two female companions - also Germans - was also cut.
Krabi police are today looking for the assailants, with local businesspeople alarmed about the attack. Krabi has a reputation for being a quiet place where violent attacks on tourists are even more rare than on Phuket.
Investigating officer Lieutenant Jamlern Suwanchat, of Krabi City police, said today that the injured German woman and two friends were aiming to head to Phi Phi island on Sunday.
''About 2.30am on Sunday morning the three women went for a walk to a convenience store a couple of hundred metres from their guesthouse,'' the lieutenant said.
''A motorcycle pulled up with two men on it. One of the men brandished a knife and tried to slash the strap of a shoulder bag that one of the women was carrying.
''In the moments that followed, at least one of the women was badly cut.''
The motorcycle riders escaped with a small amount of cash, a mobile telephone and a camera, Lieutenant Jamlern said.
Staff at Krabi Hospital confirmed today that two of the women were treated for wounds in the Emergency section before being speedily transferred to Bangkok Hospital Phuket, about 90 minutes away by road.
It is understood one of the women - Hanna Zerlant, 21 - suffered a serious cut to her thumb that required surgery on Phuket to save it.
A second woman, Sina Beckert, 21, was slashed on at least one arm, Phuketwan has learned. Their companion was unharmed.
A staffer at the Bai Fern Mansion guesthouse in Chao Fan Road, Krabi City, confirmed today that the three young women checked in on Saturday with the intention of only staying one night before heading to Phi Phi island.
Lieutenant Jamlern said: ''It is shocking to us that this kind of incident would happen in Krabi. This is usually such a quiet and safe destination.''
There were no security cameras along that stretch of road, and no early clues to the identity of the attackers, he said.