British police say they are investigating bomb threats that dozens of British universities have received via email.

Metropolitan Police also say they believe the threats may be linked.

A spokesman at Cambridge University confirmed Sunday that it has been receiving almost daily threats by email in the past three weeks. He said the university made the necessary searches each time and evacuated buildings on three occasions as a precaution, but so far none of the threats have been substantiated.

David Alder, a spokesman for Bristol University, said that institution has received about 12 similar emails since late April and that all have proved to be hoaxes. The emails did not specify any reason or cause, he said.