A ceremony was held Monday to mark nine years since Massachusetts Institute of Technology police officer Sean Collier was killed in the days after the Boston Marathon bombings.
The MIT Police Department laid a wreath at the Collier Memorial, located on the Cambridge university's campus -- just a couple of miles from Copley Square where thousands of runners crossed the Boston Marathon finish line on Monday.
"We paid tribute to Sean who exemplified what we aim to be as officers & community members," MIT police wrote on Twitter. "Sean’s heroic legacy, tremendous smile & spirit will never be forgotten."
Cambridge police also shared photos on Twitter of a wreath that their department had placed Monday to mark the anniversary of Collier's death, writing, "We will never forget you, Sean."
Collier was on duty the night of April 18, 2013, when he was fatally shot near MIT's campus by the two suspects responsible for the Boston Marathon bombings.
In early March, the Supreme Court reinstated the death sentence for convicted Boston Marathon bomber Dzhokhar Tsarnaev, who had been convicted of all 30 charges against him, including the killing of Collier during the manhunt that ensued following the bombings.