The terrorist attack in Vienna on Monday night which has left three people dead and at least several wounded was in the vicinity of the Maltese embassy, Foreign Minister Evarist Bartolo said on Monday.

Speaking on Facebook, the minister said two employees are working from home to avoid dangers.

In the attack, gunmen suddenly opened fire in Vienna, brutally shattering the calm of the Austrian capital.

At least three people were killed, with several wounded, when attackers opened fire in six central locations.

Witnesses said they saw a man shoot "like crazy" with what appeared to be an automatic weapon, before police arrived and opened fire. 

With one assailant shot dead, the city's mayor urged people to remain indoors as police said a huge manhunt was underway for one of the attackers.