A Brooklyn man has been charged with manslaughter in the death of his 2-month-old son, police said Monday.

Police said they found little Llord Nikolaii Major unconscious and unresponsive when officers responded to his father’s home in Bushwick around 6:45 a.m. Friday.

Quincy Pierre, the boy’s father, initially told police that he and the infant fell asleep together and when he woke up, the baby wasn’t moving, police sources said.

But according to grisly details in a criminal complaint, police said Pierre, 19, admitted that he “twisted” both of Nikolaii’s legs” and “forcibly pressed down” on his “right rib area” with his hands.

The complaint alleges that Pierre also admitted to “twisting” the baby “rapidly.”

The child was taken to Wyckoff Heights Medical Center, where he was pronounced dead, cops said.

The city medical examiner Monday ruled the he died of multiple blunt force injuries and ruled the death a homicide.

Pierre was charged Saturday with two counts of manslaughter and one count of endangering the welfare of a child.

“It’s a shock to me, just a shock,” said Lisa Saunders, who manages an adult day care facility down the street. “He could have gotten help. If I would have known personally I would have took the baby myself.”