PALO ALTO (CBS SF) — A Caltrain struck and killed a 15-year-old Palo Alto High School student in Palo Alto Monday morning.

Northbound train No. 309 fatally struck the person at about 6:25 a.m. on the tracks south of Churchill Avenue. A preliminary investigation determined the case is a suicide, according to Caltrain officials.

The fatality initially shut down Caltrain service in both directions. The southbound tracks reopened around 7:15 a.m. and trains single-tracked through the area.

Caltrain service resumed in both directions as of about 9 a.m.

The fatality is the eighth on Caltrain’s right-of-way so far in 2015. There were 10 in all of 2014, eight of which were determined to be suicides, agency officials said.

Over 36,600 Americans died in motor vehicle accidents in 2010, while nearly 5,000 more — nearly 38,400 — died by suicide, according to the U.S. Centers for Disease Control and Prevention.

Here are some of the warning signs of suicide:

Talking about wanting to die or to kill oneself.

Looking for a way to kill oneself, such as searching online or buying a gun.

Talking about feeling hopeless or having no reason to live.

Talking about feeling trapped or in unbearable pain.

Talking about being a burden to others.

Increasing the use of alcohol or drugs.

Acting anxious or agitated; behaving recklessly.

Sleeping too little or too much.

Withdrawing or feeling isolated.

Showing rage or talking about seeking revenge.

Displaying extreme mood swings.

If you or someone you know is thinking about suicide, contact the National Suicide Prevention Lifeline at 1-800-273-TALK (1-800-273-8255) to be connected to a skilled, trained counselor at a crisis center in your area, anytime 24/7 or locally, go to www.SFsuicide.org or call (415) 781-0500.

Facebook recently rolled out a new feature designed to help prevent suicides by allowing users to quickly alert someone if a friend appears to be thinking of harming themselves.

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