ARVADA, Colo. -- Classes at Arvada High School were delayed Friday after someone drove a car through the front entrance of the school building and left it there.

The Arvada police and fire department were called to the school near 66th and Wadsworth at about 4:30 a.m. when a newspaper deliveryman noticed shattered glass, smashed doors and the blue Honda sitting inside the hallway.

No one was inside the wrecked car or the building.

"This was completely just a senseless act of vandalism. I find it to be extremely cowardly on the individual's part and I fully expect we will find out who did it," said Arvada High School principal Robert Lopez.

Arvada police say the car was stolen from the school's parking lot. A student at Golden High School had left her car on the lot overnight when, after attending the All-County Band Festival, she discovered that she had locked her keys inside.

Police say the vandals broke into the car and then rammed it through the school's glass doors, abandoning the vehicle inside the lobby after they had slammed into the wall. Officers found blood on the ground.

The Jefferson County School District at first called in a building inspector who determined that there was too much damage to the front entryway to try and run 1,600 students in and out of the building, so officials decided to close the school. But then, the damage was reassessed after officers pulled the car out around 6:30 a.m. The principal was told that there was not that much structural damage, so he delayed classes while the debris was cleaned up.

The cost of damage is estimated at $50,000.

Students who know anything about the case are asked to contact Arvada police.