FORT LAUDERDALE, Fla. -

The trial began Monday for a 23-year-old man accused of killing his adopted mother.

Gerard Lopes Belmonte is charged with premeditated murder in Natalie Belmonte's death. Belmonte was Lopes Belmonte's cousin. She rescued him from Guyana after his father died.

"That man is guilty of murdering his mother," said assistant state attorney Adriana Alcalde. "The defendant strangled her, beat her, killed her, and then threw her away with no panties and her skirt lifted up to here like if she was garbage."

Prosecutors said the pair was seen on surveillance video going to a graduation party. Jose Reyes, Lopes' public defender, said his client blacked out drunk that night in 2011.

"He says I went to a party with my mother, I drank too much, and I don't remember what happened last night," said Reyes.

Alcalde said blood was found in the hallway and guest bathroom.

"You're going to hear the bedroom area is where she bled the most," she said.

A neighbor's surveillance camera captured a person dragging a body-sized bag into Belmonte's car. Her body was found in nearby woods three days later.

"Part of her scalp was off. She had a ragged cut on her left, front jaw. She was beaten," said Alcalde.

Lopes Belmonte's clothes were found in a dumpster. Prosecutors said the clothes include plaid shorts seen in the surveillance video.

"Those shorts are drenched in her blood," said Alcalde.

Last week, prosecutors said Lopes Belmonte raped his adopted mother, then killed her to cover it up. At the hearing, it was revealed that DNA tests showed Gerard Belmonte’s semen was found inside his mother’s body. Alcalde didn't mention that evidence Monday.