Tamale, Aug. 12, - Taxi drivers in the Tamale municipality have withdrawn their services to protest against "stringent measures" adopted by the police to enforce traffic regulations. The taxi drivers accused the police of arresting them at gun point and extorting ''huge sums of money'' from them. The strike has left many people stranded, and the desperate ones are walking several kilometres to their destinations. The problem is compounded by the lack of alternative city transport. The Northern Regional Commander of the Motor Traffic and Transport Unit (MTTU), Nana Kwame Amponsah, described extortion allegations against the police as false and a calculated attempt to sabotage the police to rid the city of ''ramshackle vehicles''. But the police are not rpt not deterred by the strike action, and ''the exercise will continue unabated'', he said. The police for the past week have embarked on an exercise to arrest vehicles that are not roadworthy and those without valid documents. Over 70 vehicles - mostly taxis - have been impounded and their drivers are to be prosecuted soon. Some of the offenders have already been fined between 20,000 cedis and 110,000 cedis. The Industrial Relations Officer of the GPRTU, Mr Salifu Masahoodu, told the GNA that the strike was illegal and that drivers were being prevailed upon to call it off and to channel their grievances through the appropriate authorities. At the time of filing this report, the taxi drivers were yet to call off the strike.