Three people were arrested at Tobey Hospital in Wareham, including one accused of stabbing a Cape Cod woman.
The young woman accused of attacking her was also at the hospital, and in fact was brought in the same car as the victim.
Karis Callanan of Plymouth was arrested at the hospital and charged with attempted murder.
Authorities say the two know each other.
Two other people were taken into custody at the hospital, John and Marie Ditalia of Bourne.
Police say they saw the woman assault the man in the hospital parking lot.
When officers arrested her, John Ditalia apparently charged at them.
Their relationship is unknown, though police say they’re connected to the stabbing, but aren’t saying how.