SWAT team descends on Hyde Park street; alleged girlfriend beater flees
WBZ Radio reports heavily armed Boston Police rushed to Wood Avenue around 5 a.m. when a woman reported she had escaped her boyfriend, who had been beating her in the face and that he was inside, with a weapon and a hostage. Neighbors were evacuated, police went in and nobody was inside, WBZ says.

Noise distraction devices
The Globe reports that before storming the building, police first set off a couple of explosions to, well, make a lot of noise to distract the alleged hostage-taking thug.
He held her in a headlock as he tried to load a gun
Boston Police have released more info on the incident:
Ramon Rosarion, 50, of Roxbury is sought.