Police have arrested a 31-year-old man after - they say -- he called 911 and confessed to stabbing his mother to death late Saturday night inside his Midwood apartment.

According to investigators, Richard Cohen stabbed his widowed mother, Anne Cohen, 64, more than 40 times in the neck and torso, during her visit to the ground-floor apartment, he's been sharing with his live-in girlfriend at 1220 Ocean Ave.

This was just before 11 p.m.

Mrs. Cohen was rushed to Community Hospital, where doctors pronounced her dead. Cohen, who has a history of mental illness, has been charged with second-degree murder.

Betsy Fares, 48 -- a neighbor from Mrs. Cohen's Bath Beach neighborhood -- who's known the family for more than 20 years, says Richard Cohen would fight constantly with his mother about money. She says Mrs. Cohen told her that her son, lost his job recently.

According to Fares, Cohen held his mother hostage as recently at four years ago.

"The swat team was here twice, he held her at knife-point in the house a couple of times," she said, adding Mrs. Cohen was a petite woman, who was no match for her mentally disturbed son, which Fares described as a "big kid."

Meanwhile, Mrs. Cohen's other son, Michael Cohen -- who had been living with her at the family Bay 25th Street home since her psychologist husband died about 10 years-ago -- was reportedly so distraught about his mother's murder, he had to be taken away by ambulance.

Additional Reporting By Ellyn Marks