The city of Somerville announced it is suspending the operating permit of the Holiday Inn’s Night Games Lounge for lighting and safety violations related to the building’s emergency backup systems. The decision followed an investigation prompted by a fight involving 10 to 12 women broke out early Friday morning. City and fire inspectors revoked the lounge’s certificate of occupancy because of problems with the emergency lighting system, the city said. “We take incidents like these very seriously, and intend to take every action necessary both to address this particular issue, and to prevent similar incidents from occurring in the future,” Mayor Joseph A. Curtatone said in a statement. The Somerville Licensing Commission is expected to hold a hearing on whether the club’s alcohol and entertainment licenses should be modified, suspended, or revoked. A New Year’s Eve party at the club was canceled because of the fight.