"Since it is outdoors winds are also dispersing some of the gas," Nils Norling of the Skåne police told news agency TT.
Paul Bjurehag of the regional rescue services said: "There is always a risk of explosion, which is why we have cordoned off the area, but with natural gas the risks are somewhat smaller than with other kinds of gas."
A preschool was opened up to house the evacuees.
A spokesman for gas company Eon told TT that the event will not have any major consequences for Eon clients.
"Unfortunately this happens now and then. You should always contact Eon and ask if there are any gas mains before you start digging," said Mattias Hennius of Eon.
At 7.15 PM the leak had been contained and residents were seen returning home.