The Yale Police Department confirmed details Monday concerning the Friday night arrest of two minors on the steps of the Art and Architecture Building.

The two boys, ages 12 and 13, were apprehended after police discovered they were hiding a knife and a pellet gun in their clothes, YPD Lt. Michael Patten said. Both boys were arrested for simple trespass and carrying a dangerous weapon. The boy with the pellet gun was also arrested for carrying a facsimile firearm.

Patten said the police received a call a little after 9 p.m. Friday from a student who described a couple of boys loitering outside the building. When the officers arrived, they saw the boys were fidgeting a lot, Patten said, and a knife fell out of one of the boys’ pockets. He said that when the officers asked the other boy to show his hands, a pellet gun fell out of his sweatshirt sleeves. The officers then arrested the boys, who were returned to their parents and who will have to appear in juvenile court.

Patten said the student who alerted the police Friday night acted as everyone should when they see suspicious behavior on campus.

“This incident is a good example, to steal a slogan from the [Metropolitan Transit Authority], of ‘If you see something, say something,’” he said. “Here’s someone who saw some boys they thought were up to no good, and, lo and behold, they were up to no good. The system worked in this case.”

Ellen Cameron ’08, who witnessed the arrest, told the News Sunday that she had walked past the two boys on the steps outside the building when she entered at 8:30 p.m. but she had not paid special attention to them since there had been many people around.

But when she left the building an hour later, she said, only the boys and police remained outside the building. The officers told her and Katie Wiacek ’08, who left the building with her, that they should not leave the building alone at night.

Patten said architecture students’ concerns after the incident highlight the reasons why students should be careful when walking outside late at night.

“We just remind people of the services the University has available to them, like the minibus and 2-Walk,” he said. “Try not to walk by yourself if at all possible.”

Architecture students said they commonly leave the building alone late at night. While some students said they are not generally afraid of walking home during those hours, others said they had already been concerned before the arrests.

“A lot of people are afraid to walk home at night,” Alexander Sassaroli ’08 said. “It’s really dark here at night, especially with the fencing.”

Because of construction next to the building, the sidewalk on one side of the entrance has been blocked, leaving only a narrow walkway for pedestrians. Many architecture students said they understand the need for the construction, but wish that the entrance area were not so constricted. Other students said they would like a bit more lighting on the walkway, though they noted that lighting has improved recently.

“There weren’t lights around the fence in the beginning, but at least they have lights now,” Wiacek said. “As long as there are police patrolling around here [I feel safe].”

Patten said the YPD does not plan to adopt new procedures or increase its presence in the area. The department already has a significant presence in the area, he said.