UPDATE: Police say the shooting started after members of rival Boston gang members bumped into each other in Macy's, the Herald reports.
Police locked down the South Shore Plaza tonight after gunfire erupted inside. State Police report:
Preliminary information suggests two individuals were involved in some type of altercation and shots were fired by one or both of them. At least one of them appears to have been injured. Preliminary investigation indicates that both individuals most likely ran from the mall immediately after the incident but that has not been definitively confirmed. Both individuals are at large. Teams of state troopers and Braintree officers are currently searching the mall.