Three Turks drowned and one was rescued Monday near a beach in Spain's southern Mediterranean city of Marbella where three days of mourning was declared, Spanish officials said.A group of 10 disabled students and their two teachers, all from Turkey, had arrived to Spain last week to participate in a two-week program for the mentally-challenged.The group was swimming on Monday afternoon in Marbella's La Venus beach when the 18 and 19-year-old students and their 29-year-old teacher drowned.Another 18-year-old was rescued and hospitalized in serious condition, according to information obtained by The Anadolu Agency correspondent.An emergency worker stated that there were no lifeguards or coastguards in the area where the incident happened.Spanish police have launched an investigation. Turkey's Ambassador to Spain Ayşe Sinirlioğlu said she was in contact with Spanish authorities, as well as the Turkish group, and added that she would send a diplomat to the area.Marbella declared threes day of mourning following the deaths while Mayor Angeles Munoz expressed his condolences to the victims' families via Twitter. Spanish media outlets pointed out that there were no lifeguards on the beach at the time of the incident and no flag indicating the risk of drowning. Municipality official Felix Romero acknowledged a lack of measures and attributed it to it being the off-season, noting that the beach would be officially opened on July 15. Locals said strong winds were battering the coast over the past two days leading to large waves.A Turkish official told media outlets that Nalbant, the teacher, was not swimming at the time of the incident and jumped into the water to rescue the students when he spotted them drowning.Anadolu Agency reported that the students were only dipping their feet into the water when they were dragged away by a sudden surge of waves. The three bodies are scheduled to be flown to Turkey on Wednesday.