The man was shot dead by an off-duty police officer following the two attacks at a shopping centre and nearby residence.
A man has been shot dead by an off-duty police office after stabbing two people to death and injuring another two.
Two people were knifed at a shopping mall outside Boston by a suspect who crashed a car into the front of a store.
Two other people were stabbed at a nearby residence, police said.
Witnesses told local television station WHDH-TV that they saw people running out of the mall and heard gunfire.
Taunton Fire Department dispatcher Mike Marshall said reports started coming in around 6.37pm and that the department sent out "a lot" of ambulances.
WHDH-TV reported that people in the area, about 40 miles south of Boston, saw police officers with guns drawn and that the mall had been evacuated and put on lockdown.
The motivation behind the attacks was unclear.