Kolkata/Contai: Mass resignations are causing civic bodies to collapse across Bengal, including in Trinamool strongholds, exposing growing organisational strain within the party.On Monday, North Barrackpore municipality was pushed to the brink after 16 councillors tendered their resignations. The churn has also intensified in Bhatpara, Kanchrapara, Halisahar and Garulia. Most resigning councillors described their move as a "matter of moral responsibility."In Abhishek Banerjee's stronghold of Diamond Harbour, eight TMC councillors resigne. Earlier, the Contai municipality board was dissolved after 14 TMC councillors resigned. Meanwhile, Mamata Banerjee on Monday urged party councillors to stay united as resignations unsettled several civic bodies run by the party.