Investigations into the alleged assassination attempt on the life of the NDC Member of Parliament for Tamale South, Haruna Iddrisu have become inconclusive.The Criminal Investigations Department (CID) of the Ghana Police Service says the investigations have stalled because the key witnesses in the case have failed to cooperate with the police.The alleged plot was first published by the Ghanaian Observer newspaper in May 2007 and later carried on other radio stations and newspapers.The story generated intense public interest, but investigations to determine the veracity of the alleged plot has not yet taken off.Speaking to Joy News, ACP Tokor of the CID said all the parties in the case including the newspapers that originally carried the news have failed to assist the police with investigations.