The threat was unrelated to animal testing carried out at the Clinical Research Centre (CRC), the front of which was blown off in a dynamite explosion at 2am.
"The animal rights activist lead has gone cold. There is instead another threat that we consider a lot more interesting," said police investigator Willy Persson.
The investigator refused to elaborate further on the nature of the threat, which was communicated to the police via telephone shortly after the bomb exploded. Persson said the blast was caused by a single stick of dynamite that was powerful enough to destroy a large number of window panes and leave clear marks in the stone paving where it had been placed.
"This type of criminality is hard to get at, but apparently there is a surveillance film. If we're lucky there'll be something on the film," said Persson.
Police had previously been considering the possibility of a link to animal rights activists.
"Of course that's one of our theories but it's too early at this stage to focus on just one theory," Martin Carlsson at Skåne police told Svenska Dagbladet on Monday morning.
The bomb attack has been classified as negligent endangerment and the building has been sealed off for forensic examination.
The police currently have no suspects in the case and no witnesses have come forward.