Burbach (dpa / lnw) – A 31-year-old died in the outdoor pool in Burbach (Siegen-Wittgenstein district). The cause of death is still unclear, the police said on Thursday. Lifeguards discovered the lifeless man in the water in the morning. Attempts to revive him were unsuccessful, a police spokesman said. According to initial findings, the man is said to have previously undertaken diving exercises in the swimming pool. A rescue helicopter was also used.