Facebook co-founder and CEO Mark Zuckerberg and his girlfriend Priscilla Chan visited the infamous "Hanoi Hilton" prison in Hanoi Thursday, two local news web sites quoted witnesses as saying.
The Dan Tri web site quoted Tran Ngoc Bich, a tour guide at the prison, which was later transformed into a museum, as saying that the billionaire was wearing "T-shirt, jeans and trainers - like any other normal tourist" when he arrived at around 11 a.m.
Bich said Zuckerberg and Chan were there with a group of about 10 other tourists who "were also very excited at seeing this talent young man."
A report of the VnExpress news web site quoted an unnamed salesperson of a shop that sells Vertu luxury mobile phones as saying that the Facebook CEO visited his shop on Thursday afternoon.
His bodyguards, however, refused to let his fans take photos with him, the report said.
VnExpress said, without quoting sources, that Zuckenberg was granted with a two week tourist visa to Vietnam on December 16.
It also quoted Huynh Kim Tuoc, Facebook representative in Vietnam, as saying that he had not been informed in advance about Zuckenberg's visit.