Posterior Urethra
The prostate, surrounding the posterior urethra, is a gland that secretes the fluid containing sperm into the urethra in men. Disorders in the prostate such as infection, enlargement or cancer may cause the bleeding. Because the bleeding may be kept within in the prostate for a while before the urination, urine color may be dark red or brown. Blood in urine is seen at the last portion of the urine.
Please see your doctor for diagnosis and treatments when you see blood in the urine or experience pain when urinating.