Unless a deal can be worked out with Lebanon, the United States promises to hunt down and put on trial a Lebanese hijacker released from a German jail 19 years into a life term for hijacking a U.S. airliner and murdering a US serviceman passenger. Sean McCormack, spokesman at the State Department, also said Tuesday that President George W. Bush's administration was disappointed by Germany's decision to free Mohammed Ali Hamadi, convicted in the 1985 hijacking of a Trans World Airlines jetliner. Hamadi was convicted in Germany of air piracy for the takeover of the airplane and murder for the beating and shooting death of US Navy diver Robert Dean Stethem, whose body was dumped onto the tarmac of Beirut International Airport in Lebanon. The United States filed federal murder charges against Hamadi in 1985 and asked Germany to extradite him after his capture. He was arrested at the Frankfurt airport on Jan. 13, 1987, when customs officials discovered liquid explosives in his luggage. The Germans denied the extradition request. Hamadi apparently has returned to Lebanon. His whereabouts are unclear.