METHUEN — A Massachusetts man suspected of strangling his ex-girlfriend as their 4-year-old son pleaded with him to stop has been captured in California.Massachusetts State Police say 33-year-old Emilio DeLarosa, of Lawrence, was arrested in Patterson, California, on Wednesday where he was living and working under an alias. Police confirmed through fingerprints that the man they arrested was DeLarosa.He faces a murder charge in the Sept.