JACKSONVILLE, Fla. -

Michael Dunn, the man accused of shooting into an SUV and killing 17-year-old Jordan Davis last month after an argument over loud music, has been indicted on a charge of first-degree murder. Dunn was initially charged with second-degree murder.

WJXT-TV reports a grand jury also handed down three counts of attempted first-degree murder because there were three other occupants in the SUV, and a charge of shooting into an occupied vehicle.

Dunn is scheduled to be arraigned Monday on the new charges. He's being held in the Duval County jail without bail.

Police said Dunn fired into the SUV that Davis and three of his friends -- Tevin Thompson, Leland Brunson and Tommie Stornes -- were sitting in at a Gate gas station in Baymeadows. Dunn's lawyers are considering using a "stand your ground" defense because they say the boys pointed a gun at Dunn. Police have not confirmed that claim.

DOCUMENT: Michael Dunn indictment
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Davis' father hopes a vigil Saturday at Friendship Fountain downtown will spread his message that gun laws are too loose in Florida, and had they been stronger, he says his son may still be alive.

"People that will come out and remember him, talk about him, they're able to do so, kind of get in touch with other people that feel the same way that this was a senseless shooting," Ron Davis said in a phone interview Thursday.

Davis's death has garnered national and international attention, but his friends and family say they feel the pain the worst.

"A lot of friends will be at the vigil, a lot of people say they'll be at the vigil on Saturday," said Aliyah Davis, Jordan's classmate and friend.

She organized a barbecue and said she'll be at the vigil and rally. It's not only to honor her classmate, but to help cope with his death.

"It's been a really tough time, so us getting through this together through a vigil and a cookout is really helping us cope with this," Aliyah Davis said.

Ron Davis's lawyers say this weekend's event will mark the kickoff of a new campaign called "Kill Guns, Not People."

"Guns are being used in ways that they're not supposed to be used," said Fadi Chakour, a Davis family lawyer. "That's what Ron wants to emphasize. The rest of his life he'll probably dedicate to repealing the 'stand your ground' law. He wants to have 'Jordan's Law,' which forbids people from using guns the way Mr. Dunn used his gun."

"To me, that changes the community," Ron Davis said. "And if my son can do something like that and create a Jordan's Law and help change society, the way we think about people shooting and putting our kids in harm's way, then I'd be happy with that."