Not again:
Police responded shortly after 8 a.m. to a report of shots fired at Reynolds High School.
A number of emergency vehicles have been staged near the school. A significant number of officers have arrived and surround the school.
A student tweeted that the school is in lockdown and a number of police cars have rolled up. A second student has tweeted that she heard gunfire. A third reported a police officer racing towards the school's gymnasium.
Early reports indicate there are injuries:

JUST IN: Police in Troutdale, Oregon confirm shooting at Reynolds High School; there are injuries
— @CBSNews
I'll update as information becomes available.
Link to live video.
CNN is reporting that the scene is secure, there are no deaths and that a semi-automatic weapon was used.
Multnomah County Sheriff's office now confirming the shooter is dead.
9:33 AM PT:

REPORTS: Students report on Social Media, shooter opened fire at assembly, teacher injured.
#RHSshooting, #LiveOnK2 http://t.co/...
— @Local12
10:03 AM PT:

Chief Scott Anderson: One student shot dead. Gunman also dead. #RHshooting
— @Oregonian