STAMFORD - Stamford police are searching for suspects in a violent home invasion that sent a man to the hospital early this morning.According to police, three masked men broke into an apartment on the second floor of a building on Cove Road armed with a pipe and a gun. Investigators say the men broke down the door and awoke 69-year-old James Russell. He says the men put the gun in his mouth and demanded money, then hit him over the head and in the knee with a pipe before getting away with cash. Russell was not seriously hurt. Police believe Russell's attackers knew him.