In the first such protest from among the Left Front, the CPI today voiced serious concern over alleged involvement of LF cadre in rapes in West Bengal and the state government’s ‘‘indifference’’ to women’s security.‘‘People generally have a good impression about communists and the alleged involvement of LF workers in incidents of rape is a matter of grave concern to us,’’ CPI state secretary Manju Kumar Mazumdar said here without naming, major coalition partner, the CPI(M).The recent incidents of rape at Dhantala in Nadia district, at Basanti in South 24 Parganas district and at Ghoksadanga in Coochbehar could affect the LF’s image before the upcoming panchayat elections, Mazumdar said.