A young man who lost a leg after riding on the hood of his twin brother's car was trying to stop him from driving while drunk, police said.

The driver, Anthony Dattoli, 18, was charged with aggravated assault, vehicular aggravated assault while intoxicated in a school zone, leaving the scene of an accident, and endangering an injured victim.

Dattoli was "obviously intoxicated" when he left a house party around 1:20 a.m. on June 27, investigators said in an affidavit of probably cause.

Police said he punched his sister when she and his brother Joseph unsuccessfully tried to stop him from driving.

Joseph jumped onto the hood of the car in a last-ditch attempt to stop his brother and stayed there for two to three blocks until Anthony lost control of the car and crashed into a tree at the intersection of Central Avenue and Taylor Drive in front of the Washington Elementary School.

The crash seriously injured Anthony but instead of helping, police said his brother ran away.

Dattoli was arrested a short distance away and taken to Mountainside Hospital so blood samples could be taken, according to the affidavit.

Dattoli surrendered on Monday but police did not disclose why he was not charged for over a month.

Anthony Dattoli (Essex County Jail)

In a statement to NJ.com, attorney Anthony Iacullo said Dattoli was released from custody.

Investigators said they would speak with other guests at the party and the owners of the home.

Joseph was in surgery for amputation and could not speak to police.

Joseph faces at least 10 surgeries, according to a GoFundMe page created by his sister. In an update, she said her brother is not in a coma and although he is unable to speak he nods his head when she talks to him.

"When I told him about all this money raised he looked at me with such a shocked face, and I just know he is so amazed and grateful. He is still the same Joe everyone knows and loves and is humorous even when he can’t even speak, he’s actually really hysterical," Emma wrote. "We knew he would be optimistic, because that’s just joe, but he’s literally already cracking jokes without even speaking, and I’m sure none of you are surprised."

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ

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