Some €100 in cash were stolen on Monday afternoon in a hold-up carried out by a hooded man at a Tarxien mini-market.
The police said the man, armed with a pointed instrument, walked up to the cashier and demanded cash.
The incident happened at about 12.30pm in Triq Karlu Maratta.
The cashier, a 27-year-old woman from Żabbar, and a Tunisian employee were unhurt but were treated for shock.