MONTROSE, Colo. -- Police have announced the arrest of a second teen in connection with a knife attack at Montrose High School on Tuesday.

A 14-year-old boy was arrested Thursday night for investigation of conspiracy to commit first-degree murder, as well as complicity to attempted first-degree murder, and accessory to attempted first-degree murder.

Montrose police spokeswoman Kathi Kinkel said the boy is a student at Montrose High School.

Another 14-year-old boy was arrested shortly after the attack on 17-year-old Mallory Haulman at Montrose High School. Police said she was slashed in the upper neck while walking down the main hallway at the school on Tuesday morning.

He is not a student at the school and police said it appears the attack was random and that Mallory was a random victim. She is recovering at home after undergoing surgery on Tuesday.

Police said the attacker used was a straight-edged weapon, but they have not described it further.

Police Chief Tom Chinn declined to discuss the connection between the two 14-year-olds, because the investigation is still ongoing.

The two teens are being held being held at Grand Mesa Youth Services in Grand Junction.