A Danish woman was waiting at the door to her hotel in Hanoi at midnight on Thursday when a man ran by and snatched her bag.
Ulla Merete Schmidt had taken the late bus from Noi Bai airport to the city's center, Vietnam News Agency reported.
Schmidt reportedly told police that the crime happened so fast the she could only describe her assailant as being "big."
She said she was standing alone, waiting for the owner to open the door, when the man accosted her and began to strike up a chat.
He allegedly grabbed the bag off her arm as she struggled to lean in and listen to him.
He fled on a motorbike, she said.
She said the bag contained around US$73 in US dollar and dong notes, her passport and other personal papers.
The owner of the hotel who took Schmidt to a nearby police station said that by the time she entered the hotel, the alleged perpetrator had fled.
The hotel owner, who was not identified, said he took her to the Danish embassy in the morning so she could obtain her necessary travel documents.
Police said they are investigating.