The 25 lives lost in Southern California's worst ever communter rail disaster were remembered on its tenth anniversary Wednesday in ceremonies at Union Station and in Chatsworth near where the Metrolink train collided head on with a freight train.

In Chatsworth, the tolling of a bell that had been aboard Metrolink 111 began at 4:22pm, the time the collision occurred, and rang once for every victim. For each, a loved one provided glimpses into lives cut short.

"This is a day we live every day and every year," said Angela Hefter, whose 18 year old son Jacob Hefter was among the train passengers who did not survive.

The force of the collision had pushed the locomotive at the head of the Metrolink train into the passenger car immediately beihind it. A dozen rail cars from the two trains derailed, leaving a scene of devestation.

Emergency responders struggled to locate and extricate those trapped inside crushed and twisted wreckage. It took nearly 24 hours before the last of the deceased was removed.

The repercussions were felt nationwide, and led to Congressional action requiring safety improvements.

"Sept. 12 was a day that for me is seared in my memory," said Antonio Villaraigosa, then Mayor of Los Angeles, who remained at the scene for 26 straight hours.

Twenty-three people were pronounced dead at the scene, and two more died days later. A total of 135 people were injured. The collision remains the deadliest crash in Metrolink history, and one of the deadliest rail disasters in U.S. history.

The Union Station ceremony included about a dozens family members of crash victims and at least three people who were injured. In the probe that ensued, investigators determined that the engineer aboard the Metrolink train, 46-year-old Robert Sanchez, had been actively texting a friend, despite a ban on the use of cell phones while operating the locomotive.

The texting revelation added to the anguish for the Angela Hefter and her husband Alan. Driven to take action, they created the Jacob Hefter Foundation to educate against texting while operating a vehicle, especially teens in cars.

Investigators determined that the distracted Sanchez missed illuminated warning signals about the approaching freight train when he pulled the Metrolink commuter train out of Chatsworth station. Sanchez was among those killed in the resulting crash. As a result of the crash, federal legislation was passed mandating the installation of Positive Train Control safety systems on commuter rail lines by the end of 2015.

The deadline was later extended, but Metrolink moved ahead quickly and now operates the system on more than 500 miles of track. Positive Train Control is a computerized system that tracks the location of locomotives and alerts railroad officials of potential collisions. The system can even take over the operation of a train if an engineer fails to take corrective actions.

"This agency has worked tirelessly night and day to make sure that nothing like this ever happens again," said Kathryn Barger, a member of the Los Angeles County Board of Supervisors who also sits on the Metrolink board. "As difficult as it might be, I am proud of Metrolink for ensuring we pause to remember this day and not let it go by without reflection. It's important for us to remember. I know this tragedy weights heavily on this board and on the staff."

Two daughters of one of the crash victims, Doyle Souser, attended the ceremony and rang the bell that was aboard Metrolink train 111 on the day of the tragedy. Souser's wife, Claudia, also spoke at the ceremony.

"We're thankful for those who have worked so hard on train safety so that no one will ever have to go through this again, but we're also thankful to all of our friends and our family who have stood with us through these 10 years so we could heal and begin to learn this new normal that we did never want," Souser said.

At the event, Metrolink also unveiled a Rail Safety Exhibit that details the Chatsworth crash, recognizes the victims and first responders and explains the safety systems that have been installed in the years since. The exhibit will be on display inside Union Station until Sept. 26.