Police asked the public to be on the lookout for Kevin Thomas Parle, 33, who is wanted in Britain for the murder of a young mother who was shot dead when three men burst into her home in the northwestern city Liverpool in 2005.
He may be living in the Mediterranean town of Alicante, police said in a statement.
Police said they were also looking for Christopher Guest More, 36, who is wanted in connection for beating a man to death during an attempted robbery at a remote farmhouse in the northwestern county of Cheshire in 2003.
They are also searching for Yolanda Payan Castellanos, a 50-year-old Colombian woman wanted in Colombia, Austria and Italy for homicide, armed robbery and membership in an organized crime group.
Among the other foreign fugitives thought to be in Spain is an Albanian man wanted in Belgium and Italy for drug trafficking and armed robbery and a German man wanted for breaking into safes.
Long seen as a place where British criminals could blend in among their many resident compatriots, the sunspots of southern and eastern Spain have seen a string of major arrests in recent years.
Last year alone Spanish police detained 35 fugitives wanted by British authorities.