Investigators said Almeida stabbed Frois repeatedly, injuring himself in the process.
Frois, who relatives said has a 5-year-old son with Almeida, died at a hospital 30 minutes later.
Almeida ran off with the knife, spurring a three-hour manhunt for the 41-year-old that involved road blocks, school lockdowns, and vehicle searches.
Police caught him at 11:30 a.m. in a wooded area nearby, where he was hiding in a shed. Paramedics took him to a local hospital for treatment.
He will be charged with murder, according to the Plymouth district attorney’s office.
Frois is the 22d person in Massachusetts to die this year as a result of domestic violence - the second such death in the Brazilian community this week, according to domestic violence advocates.
“He’s a bad guy,’’ said Claudia da Silveira, the victim’s cousin. “I know he hit her a couple of times.’’
Da Silveira said her cousin would break up with Almeida, but always returned.
“He asked her, ‘Please come back. Everything is going to change,’ ’’ da Silveira recalled, standing feet from crime scene tape and blood-splattered pavement. “She didn’t deserve this.’’
Friends and relatives described Frois as a Brazilian national whose mother and son, Bruno Frois, live in a small town in the state of Minas Gerais.
Frois immigrated to the United States four years ago, working in a fast-food restaurant and with a cleaning service to send money home.
Da Silveira, who was interviewed by police, said yesterday afternoon she has the task of telling Frois’s mother that her daughter is dead.
Neighbors called Marshfield police to report the assault at 8:01 a.m. in the apartment complex of 20-unit buildings off Route 139.
State and local law enforcement officers rushed to the scene with federal agents joining the hunt.
Residents received several emergency calls, warning them to be on the lookout for Almeida.
“They gave a description of the guy and gave us the name of the guy and that he was carrying a knife and to stay inside,’’ said Barbara Stark, who lives near the apartment complex.
