The United Auto Workers (UAW) strike against General Motors (GM) is heating up on the picket lines as the standoff enters its second week. The first week saw union members arrested, presidential candidates march on the lines, and rumors floated that the strike could extend beyond a tentative agreement through the ratification vote.

Auto workers have yet to receive their $250 a week strike pay, and last week GM canceled the health insurance of all 49,000 strikers without warning. The UAW will use its $750 million strike fund and COBRA to continue most of their coverage — but the company is also feeling the pain.

The investment firm Citigroup estimates that the strike could be costing GM $50 million to $100 million per day, but Kristin Dziczek of the Center for Automotive Research says the costs will amplify as the conflict goes on.