Spain's maritime rescue service says, it has saved 56 migrants trying to make the perilous crossing of the Mediterranean Sea from Africa to European shores. <br/><br/>The service says two boats were intercepted by its search craft this morning. One boat was carrying 23 men in the Strait of Gibraltar. <br/><br/>A second boat with 33 men of sub-Saharan origin was located east of the Strait near Alboran Island.<br/><br/>Europe's border watchdog said yesterday that 22,880 migrants had arrived in Spain last year by sea, up from 10,231 in 2016. <br/><br/>It also warned it expects the number of migrants using the western Mediterranean route to Europe to increase this year.