Early-morning pranks led to felony charges for four men accused of throwing large rocks from an overpass onto I-985, Gainesville police said Wednesday. So far, two have been arrested.

No one was injured when rocks weighing 20 to 25 pounds were hurled over the railing of the Athens Street bridge between 1:30 a.m. and 2:15 a.m. Tuesday, Cpl. Kevin Holbrook said.

“We’re very fortunate that there was very little traffic on the interstate at that time,” Holbrook told The Atlanta Journal-Constitution.

But two vehicles that were hit were damaged significantly, including one that appeared to have gone under a can opener, Holbrook said Wednesday morning.

“It just peeled the top of the car right off,” he said.

Police quickly identified the four suspects believed to have been involved, and arrest warrants were secured late Tuesday.

Kyhrie Harris, 21, and Juan Peterson, 18, have both been arrested, Holbrook said. Harris was charged with two counts of criminal damage in the first degree and two counts of terrorist acts, according to police. Peterson was charged with one count each of criminal damage and terroristic acts. All of the charges are felonies.

Investigators have also charged Kendrick Perry, 19, and Michael Ellis, 21, each with two counts of criminal damage in the first degree and two counts of terroristic acts.

“We feel very confident that we’ve identified all that were involved,” Holbrook said.