Connecticut’s attorney general has sent his second warning in a month to the low-cost carrier Avelo Airlines, telling the startup it has jeopardized tax breaks and other local support by agreeing to conduct deportation flights for U.S. Immigration and Customs Enforcement.

Democrats in the Connecticut legislature, meanwhile, are working to expand the state’s sanctuary law to penalize companies like Avelo for working with federal immigration authorities.

The backlash comes after Texas-based Avelo signed an agreement early this month to dedicate three of its 20 planes to carrying out deportation flights as part of the charter network known as ICE Air. It also follows a report by ProPublica, which Connecticut Attorney General William Tong cited in an April 8 letter to Avelo, revealing flight attendants’ unease over the treatment and safety of detainees on such flights. The concerns airline staffers raised included how difficult it could be to evacuate people wearing wrist and ankle shackles.

“Can Avelo confirm that it will never operate flights while non-violent passengers are in shackles, handcuffs, waist chains and/or leg irons?” Tong’s April 8 letter asks. “Can Avelo confirm that it will never operate a flight without a safe and timely evacuation strategy for all passengers?”