Federal authorities are investigating after a cabin pressurization problem forced a Delta Air Lines flight to make an emergency landing, causing bloody noses and “stabbing” pains in some passengers’ ears, according to the company. In a statement, Delta said that Flight 1203 was diverted back on Sunday to Salt Lake City, where paramedics identified at least 10 passengers who were in need of medical attention. All were treated and released. One passenger, Jaci Purser, told Utah station KSL TV that it felt like someone was stabbing her ear. She grabbed at it, and when she pulled her hand back, “there was blood on it,” she said. Medics diagnosed her with a ruptured eardrum, and she was given antibiotic drops, steroids, decongestants, and nose spray. “It sounds like I’m underwater when I talk,” Purser said. “My hearing is so bad right now.” Another passenger, Caryn Allen, said that her husband was in visible pain on the flight, his hands clapped over his ears. “I looked about a row behind me, over on the other side of the aisle, and there was a gentleman that clearly had a very bad bloody nose, and people were trying to help him,” she said.