According to South Korean police, Jinhong Kil brought a kitchen knife and a portable fire extinguisher to a branch of Shinhhyup bank in Daejeon City of South Korea on August 18.
He threatened staff with the knife, forcing them to put all the cash available at the bank into a bag.
Then he used the extinguisher to spray other staff and ran away.
Police said he robbed 39 million won (US$29,000) from the bank in total.
His family and friends said he was in debt due to gambling.
On August 20, Jinhong fled South Korea and police later found him hiding in Vietnam's Da Nang City.
South Korean police then worked with Interpol on the case.
On September 10, Jinhong was detected in Khue My Ward in Ngu Hanh Son District.
A team of Da Nang City's police and officers from the Ministry of Public Security ambushed and arrested him.
Vietnam and South Korea signed an extradition agreement in September 2003 that took effect in April 2005, with each party agreeing to extradite any person present in its territory as requested by the other party for the purpose of prosecution.