Calgary bylaw officers are investigating after a man and woman were attacked by two large, unattended pit bulls in the city's northeast.

The attack happened on Wednesday around 9 p.m. as the pair was walking in the 4200 block of 49th Street.

The woman was bitten on the leg and the wound required stitches.

When police arrived, the dogs "came at" the police cars.  

The owners soon appeared and helped to get the dogs into the back of a police car until bylaw officers arrived.  

The dogs are being held by animal services, and there is no word yet on possible charges.

The attack comes one day after three pit bulls killed a dog and injured another in a Calgary off-leash park on Monday. Bylaw officials says charges could be laid against both dog owners.