UPDATED 2:41 P.M. (AP) -- Authorities say they have found a possible Molotov cocktail at the scene of a school shooting in suburban Denver.
Arapahoe County Sheriff Grayson Robinson said Friday that investigators are examining the device.
Robinson says the shooter shot two others at Arapahoe High School in Centennial before apparently killing himself on Friday
The sheriff says the shooter was armed with a shotgun and looking for a teacher he identified by name when he approached the school.
Robinson says the teacher immediately left the school when he learned the student was looking for him.
Robinson says the shooter then shot two students, one of whom is in serious condition at a hospital. The other is also hospitalized with a minor gunshot wound.
UPDATED 2:26 P.M. A sheriff says the student who shot two other students at a high school near Denver today had been looking for a specific teacher. But that teacher got word of it, and had left the school.
Authorities say the gunman then shot two students. One is in serious condition at a hospital. The other is hospitalized with a minor gunshot wound.
It happened at Arapahoe High School in Centennial, about eight miles from Columbine High School in Littleton. That's where two teenage shooters killed 12 classmates and a teacher before killing themselves in 1999.
Police were outside the school after today's gunfire, and students were seen walking toward the running track with their hands in the air.
One woman rushed to the school after getting a text from her daughter saying shots had been fired. She was relieved when the daughter texted that a police officer had entered her classroom and that she was safe.
Earlier: A suburban Denver student shot at least one other student at a high school Friday before he apparently killed himself, authorities said.
Arapahoe County Sheriff Grayson Robinson said the shooter entered Arapahoe High School in Centennial armed with a shotgun looking for a teacher he identified by name.
"The teacher began to understand that he was being looked at and exited the school. One student confronted the armed student and was shot," Robinson said.
The critically injured student was in surgery at a nearby hospital, said Jason Dunkel, spokesman for Littleton Adventist Hospital.
A third student was injured at the school, but it wasn't clear whether that student was shot.
Police were outside the school, and students were seen walking toward the school's running track with their hands in the air. Television footage showed students being patted down.
The school is about 8 miles east of Columbine High School in Littleton, where two teenage shooters killed 12 classmates and a teacher before killing themselves in 1999.
The shooting also came a day before the first anniversary of the school massacre in Newtown, where a gunman killed 20 children and six adults at Sandy Hook Elementary School.
Tracy Monroe, who had step-siblings who attended Columbine, was standing outside the high school looking at her phone, reading text messages from her 15-year-old daughter inside.
Monroe said she got the first text from her daughter, sophomore Jade Stanton, at 12:41 p.m. The text read, "there's sirens. It's real. I love you"
A few minutes later, Jade texted "shots were fired in our school." Monroe rushed to the school and was relieved when Jade texted that a police officer entered her classroom and that she was safe.