For the second time in two days, violence erupted outside a Dave Matthews Band concert tonight as people outside the theater threw rocks and bottles at riot police, who responded with tear gas.

More than a dozen people were arrested tonight on various charges including assault on an officer, rioting and property damage, said Sgt. Ed Pawlina. The scene was much the same 24 hours earlier when fights broke out and at least one car was torched.

Pawlina said there were no problems inside the theater but that police had to contend with "a heavy barrage" of rocks and bottles being thrown at them in parking lots surrounding the theater.

Pawlina said the situation was "out of control" at about 9:15 p.m., but most of the crowd began leaving by 11 p.m. after the concert ended.

Witnesses said police began using tear gas and pepper spray on an unruly crowd in the parking lot of the nearby jai alai fronton where a local band was playing. One crowd member threw a bottle at a police officer, hitting him in the jaw, they said. The officer responded by spraying the bottle-tosser and other officers began moving in, said witnesses.

"Before the tear gas came, everyone just started throwing bottles. They were like birds in the sky swooping down," said Jeff Bogino, 19, of Avon.

"It was like a rainstorm of bottles," said his friend, Ben Reder, 19, of West Hartford.

In another parking lot, witnesses said a dozen officers pushed hundreds away as the doors were opened. They said people began throwing objects at the officers because they felt intimidated and angry.

During Saturday's melees, police set up a command post and took crowd-control measures. A Volkswagen Jetta near the theater was set afire. Bogino said more than a dozen cars were set on fire Saturday.